Chief Pachacamac (voice)
Knuckles (2024)
Self
The Center Seat: 55 Years of Star Trek (2021)
Expedition: Back to the Future (2021)
Reunited Apart (2020)
Stars in the House (2020)
Commissioner Helgait
The Mandalorian (2019)
Lou Vitore
The Conners (2018)
Christopher Lloyd
A Million Little Things (2018)
James Cameron's Story of Science Fiction (2018)
Melvin
A.P. Bio (2018)
The Missionary
12 Monkeys (2015)
The Missionary (uncredited)
Zalmon Shaw / The Missionary
The Woodsman (voice)
Over the Garden Wall (2014)
Himself
The Real History of Science Fiction (2014)
Buenas noches (2014)
Principal McTavish
The Michael J. Fox Show (2013)
The Wizard of Oz
The Witches of Oz (2011)
Grandpa Walt Montgomery
R. L. Stine's The Haunting Hour (2010)
Live from Studio Five (2009)
Prof. Daniel Lehman
Meteor (2009)
Tesselink
Knights of Bloodsteel (2009)
Roscoe Joyce
Fringe (2008)
Dr. Leo Dreyfus
Chuck (2007)
Theodore
The Big Bang Theory (2007)
The Alan Titchmarsh Show (2007)
Head Case (2007)
Martin Kahn
Psych (2006)
Masters of Horror (2005)
Dr. Emmett Brown (archive footage) (uncredited)
VM Show Vol. 2 (2005)
Harold March
Stacked (2005)
Numb3rs (2005)
Lou Russo
Clubhouse (2004)
Professor Toone
I Dream (2004)
The Tony Danza Show (2004)
Joseph Smith
NCIS (2003)
Dr. Cletus Poffenberger
Tremors (2003)
Hacker (voice)
Cyberchase (2002)
Carmine
Law & Order: Criminal Intent (2001)
Burt Kiffle
Ed (2000)
Walter
Malcolm in the Middle (2000)
Professor Lawrence Lessig
The West Wing (1999)
Smitty (voice)
King of the Hill (1997)
Owen Kingston
Spin City (1996)
Owen Kingston (archive footage)
Sebastian Jackal
Deadly Games (1995)
Continental Op
Fallen Angels (1993)
Emmett Brown
Back to the Future (1991)
Reverend Jim Ignatowski (voice)
The Simpsons (1989)
Professor B.O.Beanes
Amazing Stories (1985)
Anthony Corrido
Street Hawk (1985)
Phillip Semenko
Cheers (1982)
The Calico Kid
Best of the West (1981)
Semi-Tough (1980)
Hans Bogardus
The Word (1978)
Reverend Jim Ignatowski
Taxi (1978)
Reverend Jim 'Iggy' Ignatowski
Self - Cameo (uncredited)
Saturday Night Live (1975)
Arnold Scully
Barney Miller (1975)
Vincent Carew
Self - Performer (uncredited)
Tony Awards (1956)