Sherlock Holmes and Dr. Watson try to track down the Great Mogul, the second-largest diamond in the world.
| Actor | Role |
|---|---|
 Ian RichardsonSherlock Holmes | Sherlock Holmes |
 David HealyDr. John Watson | Dr. John Watson |
 Thorley WaltersMajor John Sholto | Major John Sholto |
 Michael O'HaganMordecai Smith | Mordecai Smith |
 Cherie LunghiMary Morstan | Mary Morstan |
 Joe MeliaJonathan Small | Jonathan Small |
 Terence RigbyInspector Layton | Inspector Layton |
 Clive MerrisonBartholomew Sholto | Bartholomew Sholto |
 Richard HefferThaddeus Sholto | Thaddeus Sholto |
 John BenfieldMcMurdo | McMurdo |
 Gordon RollingsMr. Sherman | Mr. Sherman |
| JJohn PedrickTonga | Tonga |
 Robert RussellWilliams | Williams |
| MMoti MakanLal Rao | Lal Rao |
| KKate BinchyMaid | Maid |
 Merelina KendallMrs. Smith | Mrs. Smith |