Half-brothers Stefane and Antony despise their biological father, callous millionaire Charles Calvert. Because Charles refuses to share his wealth with his sons, Stefane and Antony ask hip American thrill-seeker Duffy to help steal the money they believe is their birthright. When Charles decides to move a large portion of his savings from Morocco to France, Duffy has an opportunity to stage a daring burglary attempt at sea.
Unfortunately the movie Duffy is not yet available on HBO Max.
| Directing | Robert Parrish | Director |
| Writing | Harry Joe Brown Jr. | Screenplay |
| Writing | Harry Joe Brown Jr. | Story |
| Writing | Donald Cammell | Story |
| Writing | Pierre de la Salle | Story |
| Production | Ron Carr | Location Manager |
| Crew | Al Lettieri | Dialogue Coach |
| Art | Michael Graham-Smith | Main Title Designer |
| Directing | Joan Davis | Continuity |
| Sound | Art Freeman | Orchestrator |
| Editing | Ray Thorne | First Assistant Editor |
| Costume & Make-Up | Betty Adamson | Wardrobe Master |
| Camera | David Wynn-Jones | Assistant Camera |
| Camera | Mickey Walters | Grip |
| Camera | John Shinerock | Focus Puller |
| Camera | Brian Cole | Clapper Loader |
| Camera | Bert Cann | Still Photographer |
| Camera | Ray Andrew | Focus Puller |
| Camera | Egil S. Woxholt | Camera Operator |
| Camera | Godfrey A. Godar | Camera Operator |
| Crew | John Richardson | Special Effects |
| Sound | Timothy Gee | Music Editor |
| Sound | Teddy Mason | Sound Editor |
| Sound | Iain Bruce | Sound Mixer |
| Art | Patrick McLoughlin | Set Dresser |
| Directing | Peter Price | Assistant Director |
| Directing | Michael Frewin | Second Unit Director |
| Production | William P. Cartlidge | Production Manager |
| Costume & Make-Up | Maude Onslow | Hairdresser |
| Costume & Make-Up | Harry Frampton | Makeup Artist |
| Costume & Make-Up | Yvonne Blake | Costume Designer |
| Art | Philip Harrison | Art Direction |
| Production | Maude Spector | Casting |
| Editing | Alan Osbiston | Editor |
| Editing | Willy Kemplen | Editor |
| Camera | Otto Heller | Director of Photography |
| Sound | Ernie Freeman | Original Music Composer |
| Production | Martin Manulis | Producer |
| Production | Harold Buck | Associate Producer |
| Writing | Donald Cammell | Screenplay |
