Peter Gallagher
Peter Killian Gallagher (born August 19, 1955) is an American actor renowned for his distinctive baritone voice, expressive bushy eyebrows, and versatile performances across theater, film, and television spanning over four decades.[1][2] He first gained critical acclaim in the independent film sex, lies, and videotape (1989) and ensemble dramas like Short Cuts (1993), later achieving mainstream popularity for his role as the principled lawyer Sandy Cohen in the teen drama series The O.C. (2003–2007).[1][3] Gallagher's career also includes notable supporting roles in films such as American Beauty (1999) as the sleazy real estate salesman Buddy Kane and The Player (1992), alongside recurring television appearances in series like Law & Order: Special Victims Unit, Californication, and Grace and Frankie.[3][2] Born in New York City to bacteriologist Mary Ann O'Shea and advertising executive Thomas Francis Gallagher Jr., Gallagher was the youngest of three children and grew up in the suburbs of Yonkers and Armonk, New York.[1][2] He pursued economics at Tufts University in the mid-1970s, while also studying music at the New England Conservatory and attending the University of California, Berkeley.[1] Gallagher's early interest in performing led him to the Boston Shakespeare Company, where he honed his stage skills before making his Broadway debut as Danny Zuko in Grease (1978).[1] Gallagher's theater career flourished in the 1980s and beyond, earning him a Theatre World Award for his role in the musical A Doll's Life (1982) and a Clarence Derwent Award for David Hare's The Real Thing (1984).[1] He later starred in revivals such as Long Day's Journey into Night (1986) and Noises Off (2001), showcasing his range in dramatic and comedic works.[1] Transitioning to screen acting, he debuted in film with The Idolmaker (1980) and broke through with Steven Soderbergh's sex, lies, and videotape, followed by collaborations with directors like Robert Altman in Short Cuts and David Mamet in The Spanish Prisoner (1997).[1][3] On television, Gallagher's breakthrough came with The O.C., where his portrayal of the nurturing family patriarch Sandy Cohen resonated with audiences and earned him a 2004 Golden Globe nomination for Best Actor in a Television Series – Drama.[3] Subsequent roles included the authoritative Deputy Chief William Dodds on Law & Order: Special Victims Unit (2013–2019), Dean Stacy Koons in Californication (2009), and the supportive husband Nick in Grace and Frankie (2015–2020).[3][2] More recently, he appeared as the music teacher Dan in Zoey's Extraordinary Playlist (2020–2021) and in films like Palm Springs (2020); in recent years, he has also starred in the Broadway play Left on Tenth (2024), the film Humane (2024), and provided voices for WondLa (2024) and Firebuds (2022–present).[2][3] In his personal life, Gallagher has been married to former music video producer Paula Harwood since May 7, 1983, and they have two children: son James (born 1990) and daughter Kathryn (born 1993), an actress and singer known for her Broadway role in Jagged Little Pill.[1][2] The family resides between homes in New York and Los Angeles, and Gallagher remains active in philanthropy, including hosting The Sandys, an annual scholarship event for UC Berkeley law students.[2]Early life and education
Family background and childhood
Peter Killian Gallagher was born on August 19, 1955, in New York City to Thomas Francis Gallagher Jr., an advertising executive, and Mary Ann Gallagher (née O'Shea), a bacteriologist.[4][1] He was the youngest of three children.[1] Gallagher's family was of Irish Catholic heritage, with his mother's maiden name reflecting their Irish roots.[5] The family lived in Yonkers, New York, before relocating to Armonk, New York, where Gallagher spent much of his childhood.[1] He attended Byram Hills High School in Armonk, where he appeared in school plays.[1]University years and early interests
Gallagher enrolled at Tufts University in 1973, graduating in 1977 with a Bachelor of Arts degree in economics.[6][7] During his undergraduate years, he immersed himself in the arts, actively participating in campus theater productions that allowed him to explore acting and performance.[8] These experiences, combined with summers spent appearing in regional theater groups near Boston, helped build his foundational skills in dramatic interpretation and stage presence.[9] A key aspect of Gallagher's university life was his involvement with the Tufts Beelzebubs, the all-male a cappella group founded in 1962, where he sang and performed alongside fellow students.[10] This participation ignited his early musical interests, as the group's innovative arrangements and performances exposed him to vocal harmony and creative expression in music.[8] Building on his Irish Catholic upbringing as a cultural backdrop, Gallagher's immersion in Tufts' vibrant arts scene fostered a blend of discipline from his economics studies and passion for performance that foreshadowed his later multifaceted career in acting and singing.[1] Although specific professor influences from Tufts remain less documented, Gallagher has credited the collaborative environment of campus theater and a cappella for nurturing his artistic development, emphasizing teamwork and improvisation as essential to his growth.[11] These formative activities at Tufts provided the practical training and confidence that propelled him toward professional pursuits in the performing arts.[12]Career
Early film roles and breakthrough
Gallagher made his professional acting debut in the 1980 musical drama The Idolmaker, directed by Taylor Hackford, where he portrayed Caesare, a young busboy transformed into a teen idol under the guidance of a manipulative promoter.[13] The film, inspired by the life of rock promoter Bob Marcucci, received positive reviews for its energetic portrayal of the 1950s rock scene, with critics praising Gallagher's charismatic performance as one of the emerging stars alongside Ray Sharkey.[14] This supporting role marked his entry into feature films following his Broadway beginnings, establishing him as a versatile performer capable of blending song, dance, and dramatic intensity.[15] In the early 1980s, Gallagher continued to build his screen presence with leading roles in independent and international productions. He starred as Michael Pappas, an aspiring archaeologist vacationing in Greece, in the 1982 romantic comedy-drama Summer Lovers, directed by Randal Kleiser, where his character navigates a complex ménage à trois with his girlfriend (Daryl Hannah) and a French archaeologist (Valérie Quennessen).[16] The film, shot on location in Santorini, was noted for its lush visuals and exploration of free love, though it garnered mixed critical reception, with some praising Gallagher's affable charm amid the ensemble's chemistry.[17] By 1985, he appeared in the British fantasy drama Dreamchild, directed by Gavin Millar, playing Jack Dolan, a brash American journalist who pursues a romantic interest with the elderly Alice Liddell (Coral Browne) during her U.S. tour commemorating Lewis Carroll's works.[18] Critics lauded the film's inventive blend of biography and hallucination, with Gallagher's energetic, flirtatious portrayal adding levity to the introspective narrative; Roger Ebert highlighted his role as a key element in the movie's emotional balance.[19] These projects showcased Gallagher's range in romantic and dramatic contexts, transitioning him from theatrical ensembles to intimate film dynamics. Gallagher's breakthrough arrived with the 1989 independent film sex, lies, and videotape, Steven Soderbergh's directorial debut, where he played John, the philandering husband entangled in a web of sexual secrets and voyeurism in Baton Rouge.[20] His nuanced depiction of a slick yet vulnerable lawyer opposite James Spader, Andie MacDowell, and Laura San Giacomo contributed to the film's critical acclaim, earning the Palme d'Or at Cannes and grossing over $36 million on a $1.2 million budget, signaling a boom for American indie cinema.[21] The role elevated Gallagher's profile, shifting him from supporting parts to more prominent character opportunities in Hollywood, as the film's success highlighted his ability to convey subtle emotional undercurrents.[22] This period reflected Gallagher's adaptation from stage to screen, where his theater training at Tufts University and Broadway experiences in shows like Hair and Grease informed a disciplined approach to character immersion, allowing him to bring theatrical depth to cinematic intimacy without overprojection.[15]Television prominence
Gallagher's television career gained significant traction in the mid-2000s, marked by his starring role as Sandy Cohen in the Fox teen drama The O.C. (2003–2007), where he appeared in all 92 episodes. Portraying the principled Jewish public defender turned corporate attorney and devoted family man, Cohen served as the moral anchor for his troubled adopted son Ryan Atwood and navigated complex family tensions with wife Kirsten and son Seth. The character's creation of "Chrismukkah"—a festive mashup of Christmas and Hanukkah—sparked a cultural phenomenon, inspiring holiday merchandise, episodes in other shows, and discussions on interfaith traditions, cementing Gallagher's portrayal as an archetype of the ideal TV father.[23][24] Prior to The O.C., Gallagher made early forays into recurring television roles, including a guest appearance in the original Law & Order episode "Point of View" (1993), though his more sustained small-screen presence emerged later. From 2007 to 2014, he recurred as Dean Stacey Koons in Californication, appearing in eight episodes as the ambitious university administrator whose professional rivalry with writer Hank Moody led to comedic and dramatic entanglements. Building on this, Gallagher took on another recurring authority figure as Deputy Chief William Dodds in Law & Order: Special Victims Unit (2014–2019), featuring in 19 episodes as the no-nonsense overseer of the SVU squad, often clashing with lead detectives over procedural and ethical issues.[25][26] In the late 2010s and early 2020s, Gallagher embraced diverse recurring parts in ensemble comedies and dramas. He portrayed Nick Skolka, the suave entrepreneur who becomes Grace Hanson's second husband, in Grace and Frankie (2017–2022), appearing in 24 episodes across seasons 3 through 7 with his character's blend of charm and vulnerability amid the protagonists' post-divorce reinventions.[27] Similarly, in Zoey's Extraordinary Playlist (2020–2021), Gallagher played Mitch Clarke, Zoey's supportive father facing progressive supranuclear palsy, appearing in 15 episodes that highlighted poignant family interactions through the show's musical format.[28] Gallagher's guest contributions extended to medical dramas, notably in Grey's Anatomy (2021–2022), where he appeared in nine episodes of season 18 as Dr. David Hamilton, an innovative Alzheimer's specialist and old acquaintance of Ellis Grey. His role drove episode-specific arcs involving experimental treatments and ethical dilemmas for Meredith Grey, adding depth to the series' exploration of neurodegenerative diseases and legacy in medicine.[29]Stage and theater achievements
Peter Gallagher launched his professional theater career immediately after graduating from Tufts University in 1977. After his Broadway debut in the 1977 revival of Hair as a chorus member, directed by Michael Butler and Tom O'Horgan, where he contributed to the ensemble's free-spirited, countercultural vibe through group numbers that showcased his vocal range and physicality, Gallagher took over the lead role of Danny Zuko in the original production of the musical Grease.[30][31] This early role, which ran for just 43 performances at the Biltmore Theatre, marked his introduction to the demands of live musical theater and helped build his reputation for versatile ensemble work.[32] His performance in Grease highlighted his strong singing voice and charismatic stage presence, drawing on his college theater experience to embody the 1950s rock 'n' roll energy central to the production.[33] Gallagher returned to Broadway in a major way with his Tony-nominated portrayal—no, wait, accurate: earning a Drama Desk Award nomination for Outstanding Actor in a Musical as the suave gambler Sky Masterson in the 1992 revival of Guys and Dolls.[34] Directed by Jerry Zaks at the Martin Beck Theatre (now Al Hirschfeld), the production featured Nathan Lane as Nathan Detroit, Faith Prince as Miss Adelaide, and Josie de Guzman as Sarah Brown, and it celebrated Frank Loesser's score with Gallagher's standout renditions of songs like "Luck Be a Lady" and "I've Never Been in Love Before," which critics praised for his smooth baritone and romantic charm.[35] The revival, a critical and commercial hit that ran for 1,143 performances and won Tonys for Best Revival of a Musical and Faith Prince's performance, solidified Gallagher's status as a leading man in musical comedy, with reviewers noting his ability to balance charm and vulnerability in the role. In 2015, Gallagher starred as the flamboyant, bankrupt producer Oscar Jaffe in the Broadway revival of the screwball musical On the Twentieth Century, opposite Kristin Chenoweth as Lily Garland, at the American Airlines Theatre under Scott Ellis's direction for Roundabout Theatre Company.[36] The production, a high-energy farce set aboard the luxury train of the title, earned acclaim for Gallagher's comedic timing and robust singing in Cy Coleman and Betty Comden/Adolph Green's score, particularly in numbers like "I Owe It All to You" and "The Twentieth Century," where his manic energy drove the show's whirlwind plot of reconciliation and theatrical scheming.[37] Critics lauded his leading-man swagger and vocal prowess, with the revival receiving Tony nominations for Best Revival of a Musical and Chenoweth's performance, while Gallagher's work was highlighted for revitalizing the role originally played by John Cullum in 1978.[38] Throughout his stage career, Gallagher's work in these productions and others, including regional and off-Broadway appearances early on, demonstrated his broad range in musical theater, from ensemble dynamics in Hair to lead roles requiring both dramatic depth and melodic delivery in shows like Grease and Guys and Dolls.[39]Recent projects and voice work
In 2020, Gallagher appeared in the time-loop romantic comedy Palm Springs, directed by Max Barbakow, where he portrayed Howard, the father of the protagonist Sarah (played by Cristin Milioti), contributing to the film's ensemble of wedding guests trapped in a repetitive day.[40] The Hulu release received critical acclaim for its witty script and performances, marking Gallagher's return to feature films amid the early COVID-19 pandemic. In 2024, Gallagher starred as Charles York in the dystopian thriller Humane, directed by Caitlin Cronenberg, where his character, a retired news anchor, announces his participation in a government euthanasia program during a family dinner, leading to chaos and ethical dilemmas.) Gallagher made a notable return to Broadway in 2024 with Left on Tenth, a play adapted from Delia Ephron's memoir of the same name, which chronicles her experiences with grief following her sister's death and the rediscovery of love with her husband Peter in later life.[41] Starring opposite Julianna Margulies as Ephron, Gallagher embodied the character of Peter, drawing on the story's themes of hope and second chances, which resonated personally with him as he reflected on the production's emphasis on resilience during a CBS interview.[42] The limited engagement began previews on September 26, 2024, at the James Earl Jones Theatre and continued into late 2024, earning praise for the leads' chemistry despite mixed reviews on the adaptation's stage execution.[43][44] Expanding into voice acting, Gallagher lent his distinctive baritone to the role of Antiquus, a wise and ancient humanoid figure in the animated sci-fi series WondLa on Apple TV+, based on the book series by Tony DiTerlizzi.[45] Antiquus serves as a mentor-like presence in the story of a young girl's quest for belonging in a post-human world overrun by alien creatures.[46] The third and final season, featuring Gallagher's contributions, is scheduled to premiere globally on November 26, 2025, concluding the trilogy's exploration of adventure and identity.[45] Gallagher has publicly celebrated the renewed popularity of his former The O.C. co-star Adam Brody, particularly in response to Brody's lead role in the 2024 Netflix romantic comedy series Nobody Wants This, expressing pride in Brody's "renaissance" while tying it to their enduring on-screen father-son dynamic from the early 2000s teen drama.[47] In an October 2024 interview, he stated, "I'm proud of him all the time as his friend and former TV dad," underscoring the lasting cultural impact of their shared television history without having viewed the new series himself.[47]Personal life
Marriage and family
Peter Gallagher has been married to Paula Harwood since May 7, 1983. The couple first met during their freshman year at Tufts University in Boston, Massachusetts, where they encountered each other in a stairwell, though Gallagher waited seven years to ask her out. Harwood, a music video producer, and Gallagher have maintained a strong partnership throughout his career in Hollywood.[48][49] Gallagher and Harwood have two children: son James, born on April 27, 1990, and daughter Kathryn, born on July 23, 1993. Kathryn Gallagher has followed in her father's footsteps as an actress and singer, appearing in projects such as the Netflix series You and Broadway productions. The family raised their children in Los Angeles, where Gallagher owned a home in the Brentwood neighborhood, fostering an environment that encouraged artistic pursuits amid their parents' involvement in the entertainment industry.[50][51][52] In September 2025, Gallagher, Harwood, and extended family members traveled to Galway, Ireland, for a reunion that celebrated their shared heritage. This trip underscored Gallagher's Irish roots, which have influenced family travels over the years, including annual pilgrimages to the west of Ireland.[53][54]Philanthropy and activism
Peter Gallagher has been a dedicated supporter of the Alzheimer's Association for over two decades, driven by his mother's prolonged battle with the disease, which profoundly shaped his commitment to raising awareness and funding research for a cure.[55] As a Celebrity Champion and member of the organization's National Advisory Council, he has organized fundraisers for the Los Angeles chapter and participated in annual Memory Walks to advance care, support, and research efforts.[56][57] In October 2025, the 41st Annual Imagine Benefit in New York City, which Gallagher attended, raised $1.3 million for the association's global initiatives, and he is scheduled to emcee the Manhattan Walk to End Alzheimer's on November 15, 2025, to bolster local programs.[58][59] Gallagher serves as co-chair of the National Board of Advisors for the Entertainment Community Fund (formerly The Actors Fund), where he contributes to advocacy and fundraising for performing arts professionals facing hardships, including health and financial challenges.[39] He has attended and supported specific events, such as the annual Jock Duncan Celebri-TEE Golf & Tennis Outing in 2019, which aids the fund's social services for the entertainment community.[60] Additionally, Gallagher has actively contributed to Broadway Cares/Equity Fights AIDS, participating in AIDS initiatives since the 1990s, including the 2020 NBC special "One Night Only: The Best of Broadway," which generated over $3 million for HIV/AIDS programs and essential services.[12][61] These efforts align with his broader theater community involvement, emphasizing support for those affected by the epidemic.[62] Drawing from his formative experiences in theater at Tufts University, Gallagher has advocated for arts education in post-career initiatives, including performances and engagements that promote performing arts programs for students.[10] In 2010, he received Tufts' Light on the Hill Award, the highest student-honored alumni distinction, recognizing his role in inspiring arts education and career pathways in the field.[63] More recently, in 2024 and 2025, Gallagher endorsed arts-related causes through appearances at university-affiliated events and benefits, such as a fundraising dinner supporting cultural philanthropy tied to educational outreach.[64] His family's private encounters with health challenges have further underscored his dedication to these public service efforts.[65]Awards and recognition
Educational honors
In 2005, Peter Gallagher, a 1977 alumnus of Tufts University, received the P.T. Barnum Award for Excellence in Entertainment from the university's Film and Media Studies program.[66] This annual honor recognizes Tufts graduates for their outstanding contributions to the fields of media and entertainment, with Gallagher acknowledged for his acclaimed acting career. The award ceremony, held on campus, celebrates such alumni through presentations and discussions that highlight their professional impact and ongoing connections to Tufts. Two years later, in 2007, Gallagher was presented with the Light on the Hill Award, the highest tribute given by the Tufts undergraduate student body to distinguished alumni since its establishment in 1995.[67] Named after founder Charles Tufts' vision of the university as a "light on the hill," this accolade honors recipients who exemplify Tufts' mission through exceptional leadership, reflection of institutional values, and humanitarian service to the broader community. The April ceremony featured Gallagher's campus visit, where he engaged with students and received a plaque, his name permanently added to the award's display in the Mayer Campus Center, underscoring his enduring ties to Tufts through mentorship and inspirational involvement. Gallagher's honors have been highlighted in Tufts publications as exemplars of alumni excellence. These recognitions stem from his foundational experiences at Tufts, where he developed early interests in theater and economics.Acting accolades
Peter Gallagher has received several notable accolades for his acting work across film, television, and theater, particularly for ensemble contributions and standout performances in dramatic roles. In film, he shared in the ensemble recognition for Robert Altman's Short Cuts (1993), earning a Special Volpi Cup at the 50th Venice International Film Festival for the cast's collective performance.[68] The following year, the Short Cuts ensemble also received a Special Award at the 51st Golden Globe Awards.[68] Gallagher further contributed to the acclaimed cast of American Beauty (1999), for which the ensemble won the Screen Actors Guild Award for Outstanding Performance by a Cast in a Motion Picture in 2000.[69] In television, Gallagher's portrayal of Sandy Cohen in The O.C. (2003–2007) earned him a nomination for the Golden Globe Award for Best Actor in a Television Series – Drama in 2004.[68] It also garnered nominations for two Teen Choice Awards for Choice TV Parental Unit in 2005 and 2006, reflecting his impact in the drama series.[68] He received a Prism Award nomination in 2006 for his performance in the episode "The Dearly Beloved," acknowledging depictions of mental health themes.[70] Gallagher's theater career includes significant honors, beginning with a Theatre World Award in 1983 for his role in A Doll's Life. He earned the Clarence Derwent Award in 1984 for The Real Thing. He received a Tony Award nomination for Best Featured Actor in a Play in 1986 for portraying Edmund Tyrone in Long Day's Journey into Night. For his leading role as Sky Masterson in the 1992 Broadway revival of Guys and Dolls, he was nominated for a Drama Desk Award for Outstanding Actor in a Musical.[71] In 2015, Gallagher received an Outer Critics Circle Award nomination for Outstanding Actor in a Musical for his performance as Oscar Jaffee in the revival of On the Twentieth Century.[71] These nominations highlight his versatility and enduring presence on stage, with aggregate industry recognition often citing his ensemble work and character-driven roles as benchmarks of excellence.[62]Filmography
Feature films
Peter Gallagher has appeared in numerous feature films throughout his career. The following is a chronological list of his roles in theatrical and direct-to-video feature films.[72]| Year | Title | Role | Director |
|---|---|---|---|
| 1980 | The Idolmaker | Cesare | Taylor Hackford |
| 1982 | Summer Lovers | Michael Pappas | Randal Kleiser |
| 1985 | Dreamchild | Jack Dolan | Gavin Miller |
| 1986 | My Little Girl | Neil | Connie Kaiserman |
| 1988 | High Spirits | Brother Tony / Martin Brogan | Neil Jordan |
| 1989 | Sex, Lies, and Videotape | John Mullany | Steven Soderbergh |
| 1990 | Tune in Tomorrow | Richard Quince | Jon Amiel |
| 1991 | Late for Dinner | Bob Freeman | W.D. Richter |
| 1992 | The Player | Larry Levy | Robert Altman |
| 1992 | Bob Roberts | Dale Petrie | Tim Robbins |
| 1992 | Watch It | John | Tom Flynn |
| 1993 | Short Cuts | Stormy Weathers | Robert Altman |
| 1993 | Mrs. Parker and the Vicious Circle | Alan Campbell | Alan Rudolph |
| 1994 | Mother's Boys | Robert Madigan | Yves Simoneau |
| 1995 | While You Were Sleeping | Peter Callaghan | Jon Turteltaub |
| 1995 | The Underneath | Michael Chambers | Steven Soderbergh |
| 1996 | To Gillian on Her 37th Birthday | David Lewis | Michael Pressman |
| 1997 | The Man Who Knew Too Little | James Ritchie | Jon Amiel |
| 1998 | Johnny Skidmarks | Art Tilson | Tamra Davis |
| 1998 | I'll Be Home for Christmas | Dalen | Arlene Sanford |
| 1999 | American Beauty | Buddy Kane | Sam Mendes |
| 2000 | Center Stage | Jonathan Reeves | Nicholas Hytner |
| 2001 | Perfume | Guido | Michael Rymer |
| 2002 | Mr. Deeds | Chuck Cedar | Steven Brill |
| 2002 | The Adventures of Tom Thumb and Thumbelina | The Mole King (voice) | Arthur Rankin Jr. |
| 2003 | How to Deal | Len Martin | Clare Kilner |
| 2005 | The Jacket | Dr. Thomas Becker | John Maybury |
| 2006 | The Shaggy Dog | Ken Hollister | Brian Robbins |
| 2008 | Center Stage: Turn It Up | Jonathan Reeves | Duane Adler |
| 2009 | Adam | Marty Buchwald | Max Mayer |
| 2009 | The War Boys | Slater | Ron Daniels |
| 2010 | Conviction | Barry Scheck | Tony Goldwyn |
| 2010 | Burlesque | Vince | Steve Antin |
| 2011 | Someday This Pain Will Be Useful to You | Paul Sveck | Roberto Faenza |
| 2012 | Step Up Revolution | Bill Anderson | Scott Speer |
| 2014 | They Came Together | Roland | David Wain |
| 2015 | Hello, My Name Is Doris | Willy Williams | Michael Showalter |
| 2016 | Center Stage: On Pointe | Jonathan Reeves | John Hyams |
| 2017 | A Bad Moms Christmas | Hank | Jon Lucas, Scott Moore |
| 2017 | Literally, Right Before Aaron | Orson Schwartzman | Ryan Eggold |
| 2019 | After | Ken Scott | Jenny Gage |
| 2020 | Palm Springs | Howard | Max Barbakow |
| 2021 | Blue Bayou | Dr. Robert Ford | Justin Chon |
| 2023 | Monster Summer | Mr. Fisher | Andy Lawrence |
| 2024 | Humane | Charles York | Caitlin Cronenberg |
Television appearances
Peter Gallagher began his television career in the early 1980s with guest and supporting roles in series and made-for-TV films, gradually transitioning to more prominent recurring and lead parts in the 1990s and 2000s. His breakthrough on TV came with the role of family patriarch Sandy Cohen in the teen drama The O.C., which aired from 2003 to 2007.[72] Subsequent credits include a mix of guest spots on established series, lead roles in short-lived shows, and recurring appearances in long-running programs. Gallagher has often portrayed authoritative figures such as lawyers, executives, and law enforcement officials. Notable later roles encompass the CIA director in Covert Affairs (2010–2014) and the romantic interest Nick in Grace and Frankie (2015–2022).[72] His television work up to 2025 includes the following credits, presented chronologically:| Year(s) | Title | Role | Episodes/Notes |
|---|---|---|---|
| 1980 | Skag | David Corelli | 6 episodes (series) |
| 1984 | Terrible Joe Moran | Joe Bonner Jr. | TV movie |
| 1988 | The Caine Mutiny Court-Martial | Lt. Cmdr. John Challee | TV movie |
| 1990 | Love and Lies | David | TV movie |
| 1993 | Fallen Angels | Mitch Allison | 1 episode ("I'll Be Waiting") (anthology series) |
| 1993 | Fallen Angels | Duke McCann | 1 episode ("Fearless") (anthology series) |
| 1994 | White Mile | Jim Miles | TV movie |
| 1996 | The Westing Game | George Theodorakis | TV movie |
| 1997 | Path to Paradise | John Anticev | TV movie |
| 1998 | Since You've Been Gone | Eliot Maroney | TV movie |
| 2002 | Path to War | Kenneth O'Donnell | TV movie |
| 2003–2007 | The O.C. | Sandy Cohen | 92 episodes (series) |
| 2004–2005 | Center of the Universe | John Barnett | 12 episodes (series) |
| 2005 | The West Wing | Steve Atwood | 1 episode (series) |
| 2007 | Californication | Stacey Koons | 4 episodes (series) |
| 2008 | Finnegan Begin Again | Mike Shaughnessy | TV movie |
| 2009 | Adam | Marty Beck | TV movie |
| 2009 | Rescue Me | Tommy Gavin Sr. | 3 episodes (series) |
| 2010–2014 | Covert Affairs | Arthur Campbell | 75 episodes (series) |
| 2011 | The Mentalist | Victor Elliott | 1 episode (series) |
| 2012 | New Girl | Gino | 1 episode (series) |
| 2013 | The Good Wife | Gordon Heffernan | 1 episode (series) |
| 2013–2017 | Law & Order: Special Victims Unit | Deputy Chief William Dodds | 8 episodes (series) |
| 2015 | Togetherness | Larry | 8 episodes (series) |
| 2015–2022 | Grace and Frankie | Nick | 24 episodes (series) |
| 2018 | The Conners | Brian Foster | 1 episode (series)[73] |
| 2018–2021 | Grey's Anatomy | David Hamilton | 9 episodes (series) |
| 2019 | The Loudest Voice | Roger Ailes | 7 episodes (miniseries) |
| 2020–2021 | Zoey's Extraordinary Playlist | Mitch Clarke | 13 episodes (series) |
| 2021 | The White Lotus | Mark Mossbacher | 6 episodes (series) |
| 2021 | One December Night | Mike | TV movie |
| 2021 | Zoey's Extraordinary Christmas | Mitch Clarke | TV movie |
| 2021–2023 | The Owl House | Dell Clawthorne (voice) | 3 episodes (series)[74] |
| 2022 | Mr. Mayor | Brett | 1 episode (series)[75] |
| 2022 | Gaslit | John N. Mitchell | 7 episodes (miniseries) |
| 2022–2025 | Firebuds | Brian Whaleson (voice) | Multiple episodes (series)[76] |
| 2024–2025 | WondLa | Antiquus (voice) | Multiple episodes (series)[77] |
| 2025 | Everybody's Live with John Mulaney | Future John Mulaney | 1 episode (series)[78] |