John Lithgow as George Henderson

Melinda Dillon as Nancy Henderson

Don Ameche as Dr. Wallace Wrightwood

David Suchet as Jacques Lafleur

Margaret Langrick as Sarah Henderson

Joshua Rudoy as Ernie Henderson

M. Emmet Walsh as George Henderson Sr.

John Bloom as Feet

Lainie Kazan as Irene Moffitt

Kevin Peter Hall as Harry

William Ontiveros as Sgt. Mancini

David Richardt as Dirty Harry Officer

Jacqueline Moscou as DMV Clerk

Laura Kenny as "Mouse" Woman

Richard Arnold as "Mouse" Spouse

Sean Morgan as Jerry Seville

Nick Flynn as Stuart

David MacIntyre as Billers

Peggy Platt as Librarian

Orene Anderson as Woman in Kitchen

William Dear as Sighting Man

Laurie O'Brien as Screaming Woman

Michael J. Loggins as "Big Gun" Man

James King as Bicycle Man

Nathaniel Ellis as Sgt. Bader

Juleen Murray as Press Woman #1

Mark Mitchell as Press Man #1

Connie Craig as Press Woman #2

Dana Middleton as News Anchor #1

Richard Foley as News Anchor #2

Larry Wansley as News Anchor #3

Steve Brodie as News Anchor #4

Mickey Gilbert as Police Officer

Tom Hammond as Police Officer

Stuart Schwarz as SWAT Officer

Justin Mastro as Vigilante

Michael Goodell as Pool Man

Chuck McCollum as Guard

Vern Taylor as Jerome

Stan Sturing as Police Clerk

Robert Isaac Lee as Kim Lee

Debbie Lee Carrington as Little Bigfoot

Britches as Little Bob

Fred Newman as Voice & Vocal Effects

William Frankfather as Schwarz