This would've been five stars easy if it weren't for an infuriating bug(?) in Case 3 that makes it way too easy to miss a puzzle, thus barring you from getting S-rank (which unlocks more puzzles and an additional backstory cut scene). The only way to get to that puzzle is to replay the entire case, and your score resets so you have to do allllllllll the puzzles again on top of going through the dialogue since there's no fast-forward mode.