Sherlock Holmes and Dr. Watson find themselves in 1890s London in this holiday special.
| Writing | Mark Gatiss | Writer |
| Directing | Douglas Mackinnon | Director |
| Writing | Steven Moffat | Writer |
| Production | Steven Moffat | Executive Producer |
| Production | Beryl Vertue | Executive Producer |
| Writing | Arthur Conan Doyle | Characters |
| Sound | Michael Price | Music |
| Camera | Suzie Lavelle | Director of Photography |
| Production | Mark Gatiss | Executive Producer |
| Production | Rebecca Eaton | Executive Producer |
| Production | Sue Vertue | Producer |
| Crew | Mark Gatiss | Creator |
| Production | Diana Barton | Line Producer |
| Crew | Steven Moffat | Creator |
| Production | Bethan Jones | Executive Producer |
| Editing | Andrew McClelland | Editor |
| Sound | David Arnold | Music |
