Each case features several locations and each chapter takes place in one location. All of the levels in a chapter are contained on the screen in that location. For example, the location might be in a house, a factory, or on a street. Levels are always ordered from left to right. To start a level, just tap on it. Levels are unlocked in sequence from 1 - 72. To move to the next location at the end of a chapter, the player must pan to the right and then tap on the door. To move to the previous location, they must pan to the left and tap on the door. If it is the first chapter, then there usually isn’t a door that leads to a prior location. Sometimes, the panning is locked and a level must be completed in order to move forward.