Dungeons can be dangerous, everyone knows that. But who among the boys ever stopped it? Tim and his friends were no exception - the Dungeon of the Jelshakh School is full of mysteries they have yet to solve. But there are also many traps, sometimes deadly. And none of them alone could cope with it.

At the same time, Tim is trying to figure out why humans have not been invited to the school for a very long time, making an exception only for him. And why none of its former graduates ever show up here again...