You walk around as the cat in an amusement park after an employee party to find clues.
You navigate your isometric character around in the environment to find clues and pressing an interaction button inspects the clue and adds it to a journal. Toggle between the real world, and the memory world by a button. In these memories you will find information on the murder, sometimes wrong, so you will have to investigate to find the truth. These memories are the center of the puzzle-mechanic in the game.
After gathering information, you have to interact with your detective companion, to continue.