The 50 Clues series offers an immersive puzzle thriller for home. Together, players must solve a case by combining items, solving puzzles, and deciphering codes. With the help of a web app, they can check their solutions and, if necessary, receive hints. Each part can be played independently, but "No Sign of Life," "Deeper Down," and "The Last Journey" tell a connected thriller: Sigrid's Search. The story is designed to be played only once, but the serial number can be activated in the app up to 30 times. In "50 Clues - No Sign of Life," players experience the first part of the story: With trembling hands, you open the box in front of you. Your sister Gro called it the Day-8 box and explained, "If you don't hear from me every week, I need help. Open this box then." She didn't reveal what her mission was before leaving, but the fear in her eyes was unmistakable. As an expert in biological warfare, she has been working for the Danish military for some time, but this time something is different. What has happened, and how can you help Gro? In the role of Sigrid, you embark on a daring rescue mission.