I liked this investigation:
The Mi'ihen Highroad Mystery is a sidequest in Final Fantasy X-2 that takes place during Chapter 4. Rin asks Yuna, Rikku and Paine to help him investigate two separate incidents that occurred on the Mi'ihen Highroad; a hover crashing on the Oldroad and the sentry machina going haywire.
You can work really hard and accuse 5 different suspects, and provide undeniable proof.
Suspect 1. Chocobo eater: they removed Chocobos from the area, and he was hungry, thus it attacked bikes with riders and tried to munch them.
Suspect 2. Propet: He wanted Chocobos to return into the area, and return of nature.
Suspect 3. Calli: She wanted to ride Chocobo, but when she arrived to get her own Chocobo friend, Chocobo eater ate him, and that retard Rin didn't allow Chocobos in the area.
Suspect 4. Riku: She jumped on mecha, and caused mailfunction. Because everyone was connected with the mailfunctioning macha, every mecha in the area had malfunction because of Riku. Remember the theme of FF X-2 was "everyone is connected". Well throwing it on Rikku would make everyone happy with exception of Rikku, and who cares about that when party gets a new dress sphere grid which is TOTALLY AWESOME and save Rikku's butt.
Suspect 5 Rin: Yuna's wicked genius has no bound and can rightfully accuse everyone even the person who asked them to make the investigation, because they were just a bunch of amateurs and how bunch of amateurs can cause any harm.
(BTW in case you are currious how she did that: She and Shinra installed watch spheres around the road, and she called Rin to investigate stuff around.
After Yuna asked him about 11 times to move from one sphere and investigate, then go back to the original sphere and investigate again, he said fuck that and went home. Yuna got unambiguous conclusion: "He claimed didn't find anything, and now he doesn't even appear when we call him for 15x, that's suspicious." Then quickly disconnected in case Rin would appear.
A bit warning don't accuse Prophet, or Rin. Or you would miss chance for certain interesting dresses.
The real culprit was of course Rin.
Well in FF X-2, you can occasionally do really weird shit, and it's interesting. For example, rescuing a person from people with assault riffles who are trying to find him because he borrowed theirs money, and din't pay back yet even when it's past deadline for few weeks already.
I miss that attention for details and minor stuff that could be done. Also it had great funny moments.
FF X-2 had blitzball, and that game.
FF XIII should have jump over adamantoise as a minigame. And it should also have some card game, to relax after beat them up stuff. Actually there was quite a lot of beat them up stuff. Dialogues, interactions, possibility to piss off government even more... I wonder why nobody even though about that.