'The Madness Of Angels' by ayalesca
Urban fantasy AU. In which John Watson is a war sorcerer recently invalided home from Afghanistan. In London he meets Sherlock Holmes, the world’s most irritating urban sorcerer and only consulting detective. There, John finds himself and Sherlock suddenly under attack by a mysterious and malevolent power-and drawn into a mystery that may tear London apart.
Magic realism and urban sorcery FTW!
http://archiveofourown.org/series/59074