An interesting Trilogy
Discworld Noir has great scenes and puzzles, and can leave you thinking for quite a long time, even off the computer. The characters are very funny (my favourite was MoonCalf) and very detailed. It is a very easy game to use, and it's quite interesting how you can change from Human to Wearwolf. The keyboard shortcuts also come in very handy.
Although the characters had great personalities, and the settings were really gloomy and cool, the animations tended to be a little too edgy and "clay figure" like. Some of the puzzles were VERY hard, and some objects are very hard to find, scanning of the screen is a must.
The Bottom Line
You are a detective, who has to investigate a series of bizarre murders happening around the glum city of Anhk-Morpork. What you don't realise is that all these murders are linked somehow, and you become one of the hunted. You meet an array of characters from trolls, wearwolves, talking dogs and dwarfs, each with it's own personality and humour.