George Segal

Harry Calder

Richard Widmark

Agent Hoyt

Timothy Bottoms

Young Man

Harry Guardino

Keefer

Susan Strasberg

Fran

Henry Fonda

Simon Davenport

Helen Hunt

Tracy Calder

Dorothy Tristan

Helen

Stephen Pearlman

Bert Lyons

Wayne Tippit

Police Captain Christie

Michael Bell

Demerest

Robert Quarry

Mayor

Quinn K. Redeker

Owner #2

Craig Wasson

Hippie Boy

Jean Rasey

Girl in Line

Tara Buckman

Coaster Attendant

Monica Lewis

Tourist Mother

Dick Wesson

Tourist Father

Bruce Kimball

Bomb Squad #1

Bruce French

Bomb Squad #2

Stephen Mendillo

Bomb Squad #3

Gene Tyburn

Bomb Squad #5

Arthur Peterson

Owner

Ron Mael

Self - Sparks (uncredited)

Russell Mael

Self - Sparks (uncredited)

Steve Guttenberg

Messenger (uncredited)

Bill Sorrells

Selby

William Prince

Quinlan