Pretty Little Liars fans know by now that they shouldn't trust anyone in Rosewood, and Andrew Campbell is no exception. Spencer's academic rival (and occasional strip poker buddy) and Aria's latest "prince charming" has officially been named a suspect by the Rosewood P.D. for kidnapping the girls. Of course, that pretty much guarantees that he didn't actually do it — even if the show is making him look extremely suspicious. The police found a journal allegedly written by Andrew that detailed why he wanted to make the girls pay, and it's definitely the kind of thing that would make Andrew look like Charles. But did Andrew even write the note? I'm positive he's not the guy behind the crime — and that A forged the note.
Pretty Little Liars is full of red herrings, and I think that Andrew is one of them. This time, I think it's Charles DiLaurentis (the real Big A) who is deploying Andrew as a decoy — and it all comes back to the Campbell farm. We know that the man who became A spent some time on the farm from his home movies, and that Andrew's family owns that farm. Charles may have even known Andrew as a child, realized the connection between Andrew and the girls, and decided to frame him for their kidnapping. A could have forged a creepy notebook to give Andrew the motivation to kidnap the girls. Without it, Andrew has very little reason to be suspected of the crime.
But is Andrew out of the game completely? That's the thing I'm not so sure about. I think that Andrew does know about A and Charles, but instead of being a part of the A team, is around to make sure that the girls are found. After all, Andrew was possibly seen lurking around Rosewood while the girls were missing — why would he do that if he were A's minion and Charles finally has all of the girls in one place? Andrew is definitely up to something, but it might not be very sinister.
Perhaps Andrew is an opportunist — he wants to hunt down A before the police do and get the credit for his brilliance. Perhaps he isn't tracking down Charles out of the goodness of his heart or for his love of the girls, but because he loves mysteries and wants to be the one to untangle them. After all, one of his favorite movies is described like this:
Whether Andrew is a villain or a hero is yet to be seen, but as of right now, we should definitely keep an eye on this guy in Season 6.