Toward the end of last week's downright killer episode of Teen Wolf, Kate leaves the hospital after Scott has basically been brought back from the dead and returns to the sewers, AKA home sweet home, to let Peter know that Scott is still alive and his reaction was pretty concerning. Peter smirkingly responds, "Thank god." Except, because he's Peter, he smolders, "Thunk... GAHD." I don't know what god Peter worships, but it seems his positivity in the face of Scott's death isn't exactly righteous. Stiles may have made the wrong move in not telling Malia what he knew about her parentage, but he was definitely right about one thing — if the last three seasons of Teen Wolf have taught us anything, it's not to trust Peter. (Life tip: Never trust anyone whose voice slowly turns British over the course of time... that is the sign of budding evil.)
In Season 3, Peter almost seemed like he was making a turn for the good guys. One can only resist the allure of Scott McCall's morality for so long, after all. Peter was helping out the pack, pulling his research weight, and stabbing Derek in the neck with his mother's claws when he asked him to. But he was also slowly regaining his strength, shifting his eyes around a lot, bribing Lydia into stabbing him in the neck with Talia's claws, and generally, seeming sneaky as hell. That's the Peter that's carried over into Season 4; the guy is clearly up to something with Kate, and the fact that he's pleased to have Scott still alive gives us an idea why. Peter told us himself in "Orphaned" that he still wants what he's always sought: "PAHHHHHHR." Oh, sorry, that's power — and there's evidence that he's specifically referring to Scott's power.
He's always been obsessed with Scott
History repeats itself
Something is up with the Benefactor
Peter says he's not the Benefactor, and maybe I'm just suffering from Beacon Hills Delusion Syndrome, but so help me, I believe him... sort of. We can't avoid the fact that his name isn't on the dead pool list, even though the Mute still attacked him earlier in the season. Also, how did he know that Scott was dying in "Time of Death" if he's lurking around in sewers? Peter at least seems to have something to do with the Benefactor. In addition to Scott having value as a True Alpha, he also has a hefty price tag floating over his head — $25 million, to be exact — and Peter's the only one who seems to be particularly interested in getting the Hales' money back. Playing ball with the supernatural enemy is not below Peter, and $25 million would be a nice little nest egg to build back up his bearer bonds fortune.