Behind Locked Doors

For 10 years he's been training to become a villain under his "Uncle's" guidance, ever since he was abducted at the very young age of 5-
At least, that's what he's been told.
When he's deemed ready, he will be allowed to step into the light of the outside world; but when he does, what will he find? And what truths will he discover along the way? Has he really been trapped here for that long?
Or is something more sinister going on?

(This is basically my first fanfic, so It probably won't be the best, but I'll try)
(Also, I'm rating this 13+ for disturbing imagery that will be described later on, such as a cat's head being smashed.)