George Segal as Harry Calder

Richard Widmark as Agent Hoyt

Timothy Bottoms as Young Man

Harry Guardino as Keefer

Susan Strasberg as Fran

Henry Fonda as Simon Davenport

Helen Hunt as Tracy Calder

Dorothy Tristan as Helen

Harry Davis as Benny Neilson

Stephen Pearlman as Bert Lyons

G.F. Rowe as Wayne Moore

Wayne Tippit as Police Captain Christie

Michael Bell as Demerest

Robert Quarry as Mayor

Richard Altman as Mandell

Gloria Calomee as Jackie

Quinn K. Redeker as Owner #2

Craig Wasson as Hippie Boy

Jean Rasey as Girl in Line

Greg Elliot as Boy in Line

Tara Buckman as Coaster Attendant

Monica Lewis as Tourist Mother

Dick Wesson as Tourist Father

Bruce Kimball as Bomb Squad #1

Bruce French as Bomb Squad #2

Stephen Mendillo as Bomb Squad #3

Larry Holt as Bomb Squad #4

Gene Tyburn as Bomb Squad #5

Arthur Peterson as Owner

Mark Thomas as Agent with Red Hat

Ron Mael as Self - Sparks (uncredited)

Russell Mael as Self - Sparks (uncredited)

Steve Guttenberg as Messenger (uncredited)

Bill Sorrells as Selby