When ex-con artist Harry claims that a secret treasure is hidden inside Candleshoe, an English estate, he creates an elaborate plan to find and steal the prize. By convincing a girl named Casey to impersonate the estate owner's long-lost granddaughter, Harry hopes to uncover the treasure's location. But when Casey has a change of heart, she must follow the clues and find the treasure, in order to save Candleshoe and stop Harry before it is too late.
| Writing | David Swift | Screenplay |
| Writing | Rosemary Anne Sisson | Screenplay |
| Directing | Norman Tokar | Director |
| Camera | Paul Beeson | Director of Photography |
| Sound | Ron Goodwin | Original Music Composer |
| Writing | Michael Innes | Novel |
| Editing | Peter Boita | Editor |
| Production | Ron Miller | Producer |
| Production | Maude Spector | Casting |
| Sound | Claude Hitchcock | Sound Recordist |
| Production | Jake Wright | Location Manager |
| Directing | Anthony Squire | Second Unit Director |
| Crew | Cliff Culley | Special Effects |
| Costume & Make-Up | Roy Ashton | Makeup Artist |
| Directing | Georgiana Hamilton | Continuity |
| Costume & Make-Up | Bob Lawrance | Makeup Artist |
| Camera | Godfrey A. Godar | Camera Operator |
| Costume & Make-Up | Julie Harris | Costume Designer |
| Sound | Peter Best | Sound Editor |
| Crew | Bob Anderson | Stunt Coordinator |
| Directing | Jack Causey | Assistant Director |
| Camera | Ray Sturgess | Second Unit Director of Photography |
| Production | Robin Douet | Production Manager |
| Art | Martin Atkinson | Set Dresser |
| Art | Albert Witherick | Art Direction |
| Costume & Make-Up | Joan Carpenter | Hairdresser |
| Sound | Ron Goodwin | Conductor |
| Costume & Make-Up | Joyce Wood | Hairdresser |
| Sound | Ken Barker | Sound Recordist |
| Production | Hugh Attwooll | Associate Producer |
