The core of Department 42 is a straight-up hidden object game with a number of adventure-style puzzles and mini-games lining its perimeter. You'll spend most of your time looking at lists of objects and scanning the scenery for cleverly hidden items. Occasionally one of these items will make its home in a menu bar at the bottom of the screen. This inventory comes into play during special puzzle scenes where your goal is to complete a few objectives by manipulating objects on the screen. Lighting an oil lamp, for example, could require finding items as well as using bits from your inventory.