The player controls Trilby
, as he breaks into buildings and burgles them. Alarms are set off if the player gets spotted by a human or camera or runs into lasers. The player has a limited number of alarms they can set off in each mission before Trilby decides now is a good time to leave. You also have an umbrella you can shock people with before they set off alarms, but shocks are limited so the player is advised to use them wisely. Trilby's umbrella can also be used to pull himself up on to the floor above him if the ceiling is thin. There are mini-games for unlocking doors and turning off cameras. The game also has a darkness mechanic. Enemies (including people and cameras) can't see Trilby if he is in dark grey areas. In the light grey areas, enemies can see him unless he sticks to the wall. In the light areas, they can see him even if he is stuck to a wall.
Whenever the player completes a mission, they get a certain amount of experience points depending on how well they did. These points can be used to gain new abilities or upgrade new ones that allow Trilby to access more places in each level. For example, there are certain doors Trilby can't get through until the player unlocks a certain ability. In the secret rooms, there is extra money, which gets you more experience points. Some of the abilities allow you to get to areas that disable lasers, which makes getting through the level quicker, and the quicker you complete the level, the more experience points you get.
At the end of each level the player gets a grade based on their time, the amount of money they collected, the amount of alarms they triggered, and the amount of tazers they used. The better their score, the more experience points they get. This adds a focus on replaying levels to improve these grades and get more experience points, which in turn allow the player to buy more abilities.
- Roll - Roll to the right or left for faster, lower movement.
- Flit - Hug the wall to hide in low light.
- Gecko Hold - Grab the ceiling as long as Trilby's strength allows.
- Sidle - Edge left and right while wall-hugging.
- Sugar Rush - Allows Trilby to use a temporary speed boost.
- Bargain Hunter - Increases the value of loots by 25%.
- Lower Standards - Allows more alarms to be triggered per mission.
- Sadist - Allows more tazers to be used per mission.
- Locksmith Levels 1, 2, and 3 - Improve your lock-picking skill, letting you open tougher doors.
- Cracksman - Safe-cracking becomes easier.
- Reasonable Doubt - Increases delay between being spotted by a human and them becoming alerted.
- Electrician - Lowers the possibility of failure when tampering with wires.
- Into Shadow - Makes Trilby only visible in full light.
- Forgetfulness - The amount of alarms triggered during a heist decreases slowly over time.