A 12-year-old orphan who has just inherited a fortune is trapped on an island with his uncle, a former British intelligence commander who intends to kill him. A young girl is the boy's only ally against the sarcastic uncle, who uses hypnotism, a pool of sharks, fire, and poisonous mushrooms as weapons.
| Directing | William Castle | Director |
| Production | William Castle | Producer |
| Writing | Mark Rodgers | Screenplay |
| Writing | June O'Grady | Novel |
| Production | Dona Holloway | Associate Producer |
| Sound | Herman Stein | Music |
| Camera | Harold Lipstein | Director of Photography |
| Editing | Edwin H. Bryant | Editor |
| Art | William D. DeCinces | Art Direction |
| Art | Alexander Golitzen | Art Direction |
| Art | Julia Heron | Set Decoration |
| Art | John McCarthy Jr. | Set Decoration |
| Costume & Make-Up | Larry Germain | Hairstylist |
| Costume & Make-Up | Bud Westmore | Makeup Artist |
| Sound | Irving Gertz | Music |
| Sound | William Lava | Music |
| Sound | Henry Mancini | Music |
| Sound | Heinz Roemheld | Music |
| Sound | Milton Rosen | Music |
| Sound | Hans J. Salter | Music |
| Sound | Frank Skinner | Music |
