Sidney Poitier as Mark Thackeray

Christian Roberts as Denham

Judy Geeson as Pamela Dare

Suzy Kendall as Gillian Blanchard

Lulu as Barbara 'Babs' Pegg

Ann Bell as Mrs. Dare

Geoffrey Bayldon as Theo Weston

Faith Brook as Grace Evans

Patricia Routledge as Clinty Clintridge

Christopher Chittell as Potter

Lynne Sue Moon as Miss Wong

Adrienne Posta as Moira Joseph

Edward Burnham as Florian

Rita Webb as Mrs. Joseph

Fiona Duncan as Euphemia Phillips

Mona Bruce as Josie Dawes

Marianne Stone as Gert

Dervis Ward as Mr. Bell

Peter Attard as Ingham

Sally James as Schoolgirl

Grahame Charles as Fernman

Michael Des Barres as Williams

Margaret Heald as Osgood

Ellison Kemp as Campbell

Albert Lampert as Schoolboy

Chitra Neogy as Schoolgirl

Stewart Bevan as Schoolboy

Cyril Shaps as Mr. Pinkus (uncredited)

Fred Griffiths as Mr. Clark

Elna Pearl as Schoolgirl

Bonnie Lythgoe as Purcel (as Bonita Shawe)

Anthony Villaroel as Seales

Richard Willson as Curly

Carla Challoner as Strong

Joseph Cuby as Sapiano

Sally Gosselin as Tuffen

Kevin Hubbard as Schoolboy

Howard Knight as Schoolboy

Jayne Peach as Jeanie Clarke (as Jane Peach)

Gareth Robinson as Tich Jackson

Roger Shepherd as 'Fats' Buckley

Stephen Whittaker as Schoolboy

Ric Rothwell as Band Member - Drums, Vocals (as 'The Mindbenders')

Bob Lang as Band Member - Bass (as 'The Mindbenders')

Eric Stewart as Band Member - Guitar, Vocals (as 'The Mindbenders')

John Clifford as Man in Market (uncredited)

Stephen Davey as Schoolboy (uncredited)

Nicholas Young as Schoolboy (uncredited)