Chuck Connors as Captain Ernie Slade

Buddy Ebsen as Glenn Farlee

Tammy Grimes as Mrs. Pinder

Lynn Loring as Manya

Jane Merrow as Sheila O'Neill

France Nuyen as Annalik

William Shatner as Paul Kovalik

Roy Thinnes as Alan O'Neill

Paul Winfield as Dr. Enkalla

Will Hutchins as Steve Holcomb

Darleen Carr as Margot

Brenda Benet as Sally

Russell Johnson as Jim Hawley

H.M. Wynant as Frank Driscoll

Mia Bendixsen as Jodi

Veronica Anderson as 2nd Clerk

Gerald Peters as Tractor Loader

Robert Donner as Dispatcher

Peter Ashton as Clerk