
A United Nations investigator crosses paths with a pair of psychic sisters on his way to Trollenberg observatory in the Swiss Alps, which has been plagued by a series of mountaineer disappearances that may be related to a radioactive cloud at the mountain's south face.

Forrest Tucker
Alan Brooks

Jennifer Jayne
Sarah Pilgrim

Janet Munro
Anne Pilgrim

Laurence Payne
Philip Truscott

Warren Mitchell
Prof. Crevett

Frederick Schiller
Mayor Klein

Colin Douglas
Hans

Andrew Faulds
Brett
Stuart Saunders
Dewhurst
Derek Sydney
Wilde
Richard Golding
First Villager
George Herbert
Second Villager
Jeremy Longhurst
First Student Climber
Anthony Parker
Second Student Climber
Leslie Heritage
Carl
Theodore Wilhelm
Fritz

Anne Sharp
The Mother
Caroline Glazer
The Child
Garard Green
The Spotter Pilot
Jack Taylor
Voice of Beheaded Climber Jim
Quentin Lawrence
Jimmy Sangster
Released