Potterlock AU: John was wounded as an Auror, not in Afghanistan. He gets away with a bit of magic in the flat, because Sherlock doesn’t pay much attention to domestic things. "He has yet to wonder how the tea makes itself each morning"
Mycroft secretly works with SHIELD. Moriarty is trying to get in league with Loki. Sherlock and Fury do NOT get along. Watson tries to teach Steve about the modern world. And Tony is not too happy about another arrogant genius hanging around.