
Locked Room
Twelve rooms, one key at a time

Lockbox Lab is a workbench, a lamp and a shelf of puzzle boxes that do not want to be opened. Every box fills the screen and every one is shut by a different mechanism: dials with click stops that must match a ring of symbols, bolts that only slide once another bolt is parked, rotating rings that have to line up a path for the light, a row of lamps that answer in a growing pattern, a gear train where turning the crank turns everything else, a sliding picture panel, a grid of lanterns, a balance that has to hang level, a marble that rolls through a maze when you tilt the board, a mirror that has to throw a beam onto a sensor and a magnetic key that has to be turned through a winding slot. Solve the mechanism, hear the lock clunk, and the lid lifts with light pouring out around a tiny treasure.
The boxes start gentle and grow into proper brain teasers, combining two or three mechanisms that depend on each other, until the last box chains five of them in a row. Nothing is random: every box is built by hand and checked with a recorded solution, and the boxes themselves give the game away if you look closely. A symbol order is engraved on the lid, a count of rivets tells you how many turns of the crank you need, a constellation shows the pattern to draw. If you are stuck, two hints per box nudge the right part.
There is no timer that can fail you, so it is a good game to relax with. Each box has a par time and up to three stars, boxes open in order from brass to crystal, and your stars, best times and treasures are kept in your browser, so a quick box on the bus and a longer session at home both count. Play with a mouse or a touch screen; on a phone the mechanisms you are not using fold into small panels you can tap to bring forward.
Find the clue, crack the lock, spot what is hidden.
Lockbox Lab
Crack thirty mechanical puzzle boxes