How to play

One envelope a day. Each envelope holds a piece of the 1986 case file and a note from the mysterious Sender. Open them in order.

Look closely. Tap photographs to enlarge them. Some envelopes contain tools (a loupe, a UV lamp, a telephone, a tape) and some contain puzzles. If you’re stuck, ask the lab for a hint.

Vote every day. At the end of each envelope, say who you suspect. On Christmas Day you’ll see how your suspicion changed.

Christmas Eve: sign the warrant. Christmas Day: break the last two seals.

Started late? Every past day is waiting for you. In a hurry? Switch to Marathon in ⚙ Settings.