My son wanted this specifically because of the key and "lock". This key "works" by pushing it straight in and it's supposed to push the plastic back and open the top. The key is so tiny and flimsy and the inner plastic is so rigid that the key kept slipping into a small space inside the key hole and getting lodged inside, meanwhile there's no other way to open the top. We almost broke the key getting in. After a few times of that fiasco I broke the inner plastic so that we'd no longer get locked out of the chest. The concept is a great idea. He had fun with the treasure.