In Guy Richie’s excellent but wildly non-canonical Sherlock Holmes series, the archvillain Moriarty is significantly less villainous than we’d traditionally seen him portrayed. He was still Sir Arthur Conan Doyle’s “Napoleon of crime”, but one who initially lives among ordinary folk, working as a professor of mathematics. This, we understood, was his genius: the ability to exert a malign influence everywhere but at no scale where he could be fingered as the originator.