Something dark and slimy is dripping through the walls of suburban London. Not the usual stuff that smells funny and can be hell on the lungs, this mould is possessed by some dark power full of bad intentions. Looks like it's another case for London's one and only trainee wizard cop, Police Constable Peter Grant, and his reluctant partner, Sahra Guleed!
Five issue mini-series.
Preceded by Rivers of London: Night Witch. Followed by Rivers of London: Detective Stories.
Collected in Rivers of London: Black Mould.
