When swimmers at a popular nudist beach begin to get picked off by an unseen terror, a devout christian investigator uncovers the terrible truth, an ancient wereshark has reawoken and will not stop until his hunger for human meat is satisfied.

Hi,

this sounds like an interesting take on Jaws I suppose. Does it have to be a nude beach? It might just limit your audience or pigeon hole it a bit - you might be going for this though. I agree picked off sounds like a sniper in the dunes. It wasn't until I read to the end I linked shark + beach etc...

When swimmers at a nudist beach become prey to an unseen terror....

"Picked off" implies to me being shot by a sniper.