Functional Secret Treasure Room!

We've all seen it in the movies - pull the special book and the bookcase moves, revealing a treasure room or secret passageway! If you pull the gray book on the left bookcase, the right bookcase shifts to the side - revealing the treasure! I would have loved to add a desk, rug, and chair in the library, but it would have taken too many pieces. 🙂 The mechanism in the back is super smooth and simple, the main components are a single gear, 1x4 toothed bar, and a long axle. Watch the video to see it in action! 🔎📚💎🤫🔍

(You will want to put the quality on 1080p.)