The department is concerned, as no reports have been received from Dr. Hoffmann for some time. In the last report from the brilliant chemist, he stated that he was on the verge of a breakthrough in the development of his truth serum. Your team sets out through the labyrinth of New York's subway tunnels. In the midst of the tracks, you find a trapdoor set into the ground. It is already open, and light is shining up from below. The formula is a challenging adventure for puzzle enthusiasts, penned by author Cyril Demaegd, with illustrations by Pierre Santamaria. The Unlock! series games allow you to experience the cooperative thrill of an escape room visit at your own gaming table, thanks to the free app that provides real-time sound effects. A tutorial and five standalone demo scenarios for printing can be found under Bonus for download.