Rolling in the Deep by Mira Grant is a novella about mermaids- and they're not nice mermaids. It's a found footage type of story about a documentary crew that sails out to the Marianas Trench to find "proof" of mermaids. It's all a hoax of course- the expedition is financed by a network (modeled off the SyFy network?) that is going to air a documentary on their "findings"- kind of like the Finding Bigfoot shows. The problem is, they do find something- and weeks later the ship is found adrift with no survivors.
This probably sounds like a spoiler but it's actually spelled out in the blurb, so it's no secret that there are no survivors. Rather the story is about what actually happened. And it's a doozy. I had seen this novella around and was curious about it, and I've been looking for stories about nasty mercreatures. This one totally delivered and my only regret was that it wasn't longer. I wanted more. The story is a bit horrifying and there's some lead up, but when the action starts it's full throttle. You know there's bad things coming and I was hoping I wouldn't be disappointed- I didn't want the ending to be anti climactic or a let down. No worries there.
It can be tough to make you care about characters in a short story like this- there's not a lot of time for characterization and Grant does a nice job making us care about some of these people. There were several that I really would have liked to have survived, and she also includes scientists in the crew. They include different disciplines- cartography, deep sea biology, etc- and the scientific underpinning provides a nice touch. The reader knows what's coming but the crew doesn't, so when the scientists begin to see hints it ratchets the tension up that much more.
If you like horror or science fiction and want to read about some truly nasty mermaids this is the perfect read.