Sherlock Holmes gets the clues he needs to solve a murder, and to prevent another one from occurring, when he finds out that a doctor owns a poisonous snake--the deadly swamp adder. Filmed on the expensive sets leftover from the movie Joan of Arc at Hal Roach Studios in Culver City and produced for the "Your Show Time" series, the short has been released as a solo feature on many DVDs that chronicle classic Sherlock Holmes films..
| Directing | Sobey Martin | Director |
| Writing | Walter Doniger | Writer |
| Writing | Arthur Conan Doyle | Story |
| Production | Marshall Grant | Producer |
| Production | Stanley Rubin | Producer |
| Sound | William Lava | Music |
| Crew | William Bradford | Cinematography |
| Editing | Dann Cahn | Editor |
| Art | Eugène Lourié | Art Direction |
| Production | Rudolph E. Abel | Production Supervisor |