This is a modern take on what used to be called an "Adventure Game" - the idea being that you move your character around and investigate clues, to take the action forward.
This is an analytical game and moves at a measured pace, controlled by your input to the puzzles that are presented - you don't move on until you solve them. So this is not a game where your reactions are tested and you have fast-moving action and shooting things. You can take your time to solve any puzzle and the "Deduction Board" halts any action, while you think about the facts that Holmes and Watson gather from the crime scene.
The game is quite faithful to the Sherlock Holmes books and features quotes from Conan Doyle, rather than being based on any of the recent films or TV series. Holmes and Watson are resolutely British and the voice acting is good, with solid English accents that would sit well in the period. Holmes is cool and aloof, self confident to the point of arrogance, while Watson is more animated and emotional. During the game, you control either character - one at a time.
The graphics are very good for the backgrounds - the interiors,buildings and London itself have been rendered in great detail, giving a real sense of atmosphere and place. The characters are a bit stiff and awkward, which is maybe why it's only a 4 star game - but then they are not rushing about, driving the action.
The game starts with a strange scene of children finding toys in a loft, which is really badly animated and they talk incoherently in strange American accents - it's enough to put you off the game, before you've even started. However, once they find Watson's diary of events, we are straight into the realistic world of Holmes' London and after brief familiarisation, we are into much darker stuff; with a tortured and mutilated body rendered in great detail, which we must explore fully.
The adult nature of the game, makes the "cutesy" opening scene all the more out of place and I would warn people not to get lulled into thinking this is suitable for children. It has full-on gore and adult themes from the off and the puzzles are pretty hard.
If you are looking for a fast-paced thriller with jokey leads like the film with Robert Downey Jr. and Jude Law - then forget it, this game is more serious and moves slowly. But if you want an intelligent game that takes the original books seriously, then this is for you. It is possible to get stuck for a long time on some of the puzzles and deductions, but there is always an answer and I think they are appropriate for the 'Great Detective'.