From Richard's list on mixing horror with other genres.
James Herbert was, for me, the king, and The Jonah is brilliant. Jim Kelso, undercover cop, is a man with dark secrets. Shunned by others in the Police, he is seen as the eponymous Jonah as everything he touches seems to go wrong. Sent off to investigate a suspected drug factory on the coast, Kelso finds himself not only fighting the drug dealers he has been sent to bring to justice, but also with his own horrifying past. Part police procedural, part terrifying horror. Brilliant stuff.