Trilby: The Art of Theft is a stealth-based freeware action game written and designed by Ben "Yahtzee" Croshaw and programmed with Adventure Game Studio (despite not being an adventure game). It stars Trilby, the eccentric cat burglar from the Chzo Mythos, a few years before the events of 5 Days a Stranger. The story does not have any relation to the Mythos other than the main character and a few sideways jokes and references.
At the beginning of the game, Trilby travels to Chapow City. There to prove his skills more to himself than to anyone else, he decides to hit the biggest target first: Dominic Perota, CEO of the outrageously amoral Protocorp. But soon things go sour, and Trilby finds himself embroiled in a conspiracy with an enigmatic entity known only as The Company...
Unlike other games involving Trilby, the story in The Art of Theft is not the selling point; it's actually nothing very special, only being told in brief bits of text before levels and a few short cutscenes. It's actually the gameplay that makes The Art of Theft shine. Your objective in each level is to either retrieve a certain object or attain a certain amount of loot, which you do by sneaking your way through screens of guards, security cameras, and trip lasers. You are only allowed to be detected so many times per level before the cops arrive, so you need to keep an eye on your visibility, represented by a light bulb in the HUD. At any time, you are either in no light (invisible), full light (visible), or partial light (invisible as long as you hug the wall or sidle slowly).
As long as you can achieve your objective, you can pass the level and move on -- however, The Art of Theft also has a grading system that marks you depending on how well you did in the level. This grading system gives you "reputation points" or RP, which you can spend between levels to upgrade Trilby's burglary skills. Getting good marks can also unlock bonus outfits for your character to wear, some of which even grant special effects.
While it may seem odd to make a prequel to a horror series that isn't even slightly horrific, that doesn't stop Trilby: The Art of Theft from being a really fun game. It's great to see Trilby again (during happier times in his life, too) and the gameplay is really solid. I've gone through this game a few times since downloading it back when it was first released, getting perfect scores in all the levels and trying to challenge myself. The story is nothing to write home about, and there's nothing particularly interesting about the presentation (sound and graphics are just "good"), but the gameplay makes it really stand out.
Probably my biggest complaint about the game is that it's too short, and when the worst thing you can say about something is that there's not enough of it, you know the developer did something right. A highly recommended game, well worth the nonexistent price tag.
Download Trilby: The Art of Theft at the Escapist.