I was on a sort of retreat.
The retreat was near the ocean.
I don't know anybody there.
Although, in the dream, I do.
Then the police show up.
They say they've discovered a body, out by the ocean.
They say there's a whole in the back of their skull.
My friends and I, wanting to be detectives, go to look at the body.
We have to sneak in, but we do so successfully.
We put on the protective gear, and gloves, and flip the body over.
Sure enough, the hair is shaved away where the hole is.
Looking close, we realize somebody's pushed their finger through the back of the skull.
It's clearly not a bullet hole.
Then I get the feeling that it's somebody on our retreat.
The three of us vow to watch each others backs, and to not be alone in a room with anyone else.
Sitting in the dining hall, we realize there's somebody behind us in the closet.
We get up, and run off.
We lock ourselves in a room (with pool toys), and try to devise a plan.

Then the dream skips ahead, and another body has been found.
Same condition as the last.

Then the dream skips ahead again (and this is the part I remember the most).
I'm in a deserted area.
It's a desolate little place, and the most frightening place I've ever been.
I'm face to face with the killer.
And yes, he's been pushing his thumb through people's skulls.
Now it's my turn, because I figured out who it was.
It was the doctor that came along on the journey.
He stares at me maliciously.
He's holding on to me, and getting ready to "finish the job".
Then I wake up.