Detective Stanley Hopkins
If there were a spin-off of Sherlock Holmes: The Next Generation, then Stanley Hopkins would definitely be the star. Stanley Hopkins appears in multiple stories in The Return of Sherlock Holmes, including the "Black Peter," the "Golden Pince-Nez," and the "Abbey Grange" stories.
This young detective is the informal protégé of Sherlock Holmes, and he often tries to apply Holmes's forensic science methods to his own cases. With somewhat limited success. Though no slouch, Hopkins isn't as über-brilliant as his mentor. But he isn't afraid to ask for help, and Holmes seems to find him "promising." Hopkins actually shows us how police work was changing in the 1890s. Forensic science was just starting to become widespread and accepted, and Hopkins seems to be on the scientific progress bandwagon with his willingness to try out Holmes's wacky ideas.
However, Hopkins isn't just a carbon copy, younger version of Holmes. Hopkins is actually a good blend of Watson and Holmes. He has Holmes's scientific streak and detective skills (somewhat), but he has Watson's nice personality and people-skills.
It's also important to note that, unlike Holmes, Hopkins is an official member of the police force. As such, he is subject to rules and regulations and the law in instances where Holmes is not. Though he uses Holmes's methods and likes to learn from Holmes, Stanley Hopkins is ultimately in a different professional position, which impacts how he solves cases.