I don't really think that would be possible at all. The only possibility for it to happen, is if someone or a group of people manage to find some king of exploit in the bitcoin code, or on the blockchain, and with so many eyes on it I really think its impossible for that to happen. Anyway, if it did happen I don't think he would be able to do anything with it. At the exact moment some exploit is found bitcoin would lose it's value, so that brilliant mind would have gotten his hands on a useless coin.