Like what Chris R. said, it is like you're a detective trying to solve a case. You have to find the clues to determine where to go next, uncover secrets, and solve riddles!
It is one of the best attractions in vegas, in my opinion. It is also well priced (be sure to get the coupon from the website!) and you get snacks/drinks while riding in the bus between crime scenes.
Well worth the money you pay for and be sure to try to find all the magic stones O.O