Anne Heywood
— Tracey Lawrence
Richard Todd
— Geoffrey Lawrence
Nicole Maurey
— Helen
Jack Hedley
— Inspector McInnes
Jeremy Brett
— Mullen (The Intruder)
Maurice Denham
— Crawford
Patrick Magee
— Simmonds
Gwen Watford
— Sister Holden
Verina Greenlaw
— Selina
Pauline Delaney
— Agnes, Selina's Mother