I've been reading Iain Rowan for a long time now going back to the heady days when Shred of Evidence was around. He's a master of creepiness and this AHMM story from the end of last year is not an exception.
Here's the set up: A man with way too much time on his hands witnesses a murder via his laptop. He calls the authorities and gives what information he has, but it appears to be a wild goose chase as far as the police are concerned. There is no evidence to corroborate the story, no missing person who might have been the victim, etc. There's some chance, of course, that the witness is insane, but, well... Isn't that always the case? The man decides to investigate for himself (after all, his sanity is in question, and one likes to clear those issues up) but what he finds out won't at all be what he expected.
Mr. Rowan has put together a tricky story and made it run like clockwork.