Hailing from Council Bluffs, Iowa, Guinan refined his acting under the Steppenwolf Theatre Company, becoming a core ensemble member in 1979 and later sharing the Broadway stage in Tracy Letts’s acclaimed August: Osage County. His screen presence spans a wide array of television guest spots, from medical drama Grey’s Anatomy to sci-fi staples such as Star Trek: Enterprise and Voyager, as well as pr… Read more
Biography written by WatchMoods, based on public sources
Known for Grey's Anatomy 2005 Constantine 2005 Hannibal 2001 The Last Airbender 2010 Series ★ 7.6 Sliders 1995
Sean Nuinn Series ★ 8 Crime Story 1986
Bruce Walsh Series ★ 7.4 The Pretender 1996
George Harper Series ★ 7.6 The Practice 1997
Mitchell Field Series ★ 7.5 Eerie, Indiana 1991
Edgar Teller Series ★ 7.2 Without a Trace 2002
Charlton Gregory Series ★ 7.2 Crossing Jordan 2001
Dr. Alexander Series ★ 7.2 Boss 2011
Governor McCall Cullen ★ 7.2 Ghostlight 2024
Janitor Fran Series ★ 7.7 Murder One 1995
Series ★ 7.3 Beyond Belief: Fact or Fiction 1997
Hank Reese (segment "Malibu Cop") Series ★ 7.2 Chicago Hope 1994
Harlan Brooks Series ★ 7.2 Dark Skies 1996
Series ★ 7 Spin City 1996
Priest #2 Series ★ 7 Alien Nation 1989
Howard Thayer Series ★ 7 The Guardian 2001
Seth Series ★ 6.9 Seven Days 1998
★ 6.7 Path to War 2003
Nicholas Katzenbach Series ★ 6.7 Mike & Molly 2010
Jack Biggs Series ★ 5.9 Empty Nest 1988
Dr. Mitchell ★ 6.5 Saint Frances 2020
Dennis ★ 5.5 Lansky 1999
Senator Estes Kefauver Series ★ 6.5 The Drew Carey Show 1995
Scoutmaster Bob ★ 5.7 Guinevere 1999
Alan Sloane ★ 6.5 Shining Through 1992
Andrew Berringer ★ 6.3 The Bedroom Window 1987
Bartender at Edgar's ★ 5.4 Miles from Home 1988
Tommy Malin ★ 5.8 Killing Kennedy 2013
Lyndon B. Johnson ★ 6 Henry Gamble's Birthday Party 2015
Larry Montgomery ★ 6.4 The Serpent and the Rainbow 1988
American Doctor ★ 5.7 The Evil Within 2017
Dr. Preston ★ 6.1 All Good Things 2010
Daniel Patrick Moynihan Start from another title 
