The main focus is Erin, the girlfriend of Crispian; it's his family they're getting together with. All is not well with the siblings and their parents. Lots of tension and fighting ensues. The plot doesn't kick off until the sister's boyfriend is shot through the window with an arrow and dies. But Erin is not who she seems to be either. She takes over quickly. And it soon becomes a cat and mouse game between those trying to kill everyone and herself. I won't give more away cuz it's just wickedly cool.
Price rents an old house from Watson Pritchard in order to host a party where he'll give 10,000$ to 5 strangers if they survive staying at the house overnight. He chooses the 5 strangers, including Pritchard. Pritchard inherited the house after his brother and sister were killed there. He's a drunk and partially insane and is the great narrator of all the impending death and doom that's going to happen!
Price also has a wife he can't stand. Is it all a plot to kill her or him or both? Is the house truly haunted like Pritchard says?
It's just good campy fun!