Paul Grogan

Bradford Dillman

Acting

Maggie McKeown

Heather Menzies

Acting

Dr. Robert Hoak

Kevin McCarthy

Acting

Jack

Keenan Wynn

Acting

Buck Gardner

Dick Miller

Acting

Dr. Mengers

Barbara Steele

Acting

Betsy

Belinda Balaski

Acting

Laura Dickinson

Melody Thomas Scott

Acting

Colonel Waxman

Bruce Gordon

Acting

Trooper

Barry Brown

Acting

Mr. Dumont

Paul Bartel

Directing

Suzie Grogan

Shannon Collins

Acting

Whitney

Shawn Nelson

Acting

Earl Lyon

Richard Deacon

Acting

Barbara Randolph

Janie Squire

Acting

David

Roger Richman

Acting

Jailer

Bill Smillie

Acting

TV Pitchman

Guich Koock

Acting

Boy in Canoe

Jack Pauleson

Acting

Father in Canoe

Eric Henshaw

Acting

Soldier

Robert Vinson

Acting

Girl

Virginia Dunnam

Acting

Water-skier

Diamond Farnsworth

Crew

Man in Boat

Bruce Paul Barbour

Crew

Screaming Woman

Robyn Ray

Acting

Dam Guard

Mike Sullivan

Acting

Brandy

Jack Cardwell

Acting

Swimming Deb (uncredited)

Sally Bondi

Acting

Dr. Robert Hoak (swimming double) (uncredited)

Eric Braeden

Acting

Scuba Diver #2 (uncredited)

Joe Dante

Directing

Hertz Clerk (uncredited)

Amy Holden Jones

Writing

Scuba Diver #1 (uncredited)

Andrew G. La Marca

Production

Army Sentry (uncredited)

John Sayles

Directing

Scuba Diver (uncredited)

Phil Tippett

Visual Effects