Alex D. Linz as Wilhelm 'Billy' von Huber

William Atherton as Ralph Stanton

James Woods as Dr. Wilhelm von Huber

Annabeth Gish as Dr. Donni McGuinness

T.J. Beacom as Ed the Bully

Austin Schwarz as Little Kid

Tony Jay as Narrator (voice)

Jack McGee as Fielding

James Benson as Gertz

Janis Benson as Gerta

Mark Moses as Alan Shepard

Michael Tylo as Guidance Technician

Michael Jeffrey Woods as Dexterity Technician

Patrick Richwood as Dieter

Scott Thompson Baker as Telemetry Technician

Wesley Mann as Rudolph

William Devane as Roger Thornhill

Joanie Fagan as Mother on Beach