Warhammer 40,000

In the far reaches of Imperial space, a ferocious warp storm approaches an Administratum world, cutting off the entire planet from the rest of the Imperium. As their towering grey spires are punished by endless rain, countless administrators, tithe-masters, and book-keepers are forced to evacuate. Among them is Greta, a lowly data-drone with a terrible secret, wanted for questioning by the sadistic Imperial interrogator Stefan Crucius. As disaster strikes and the pair are left stranded in the depths of the drowning city, captor and captive must co-operate to stand any chance of escaping. But a mysterious presence stalks them through the abandoned, flooded towers, a dread entity each must confront but which neither dare acknowledge, a Watcher in the Rain.