There are a total 92 collectibles 71 Evidence & 21 Warrants. There are collectibles on all the episodes except for episode 5 on this game. Grabbing all the Collectibles will earn you the following trophies / achievements:
Keep Digging, Detective [Bronze / 20G]
True Detective [Silver / 25G]
World's Greatest Detective [Gold / 50G]
Bring 'em to Justice [Silver / 25G]
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