In the Rivers of London series, there’s always been something of a gap between what Thomas Nightengale, The Folly’s “Gov”, was up to between the end of the Second World War and the start of the series. There’s an implication that he’s been involved in varying degrees with the Met, but not heavily – if he had, then the Met wouldn’t have had to come up with the procedures they did when Peter Grant started working out of The Met. The most recent (as of this writing) collected graphic novel in the series, Action at a Distance, helps to answer some of those questions, though not without a few problems of his own.