This game is set in old London. The first act is amazing; you play a magician in the middle of an act. The level of detail in the opening is astonishing, and is a must-play for every IF fan.
Sadly, the game goes downhill from there. It is still a very good game, but nothing can compare to the opening. You spend the rest of the game trying to understand more of your background and visiting various mundane or mysterious locales.
The game takes less than an hour to play. Some of the puzzles are very hard, and getting the 'best' solution requires that you bring some objects with you from one area to another, with no chance to backtrack if you missed them.