Bessie and her friends have taken over a remote castle for a party. But a storm rages and they become cut off by road and phone, then one of them dies. 

As they seek to cope with their terrifying circumstances, things take an even more sinister turn as it becomes clear there is a killer in their midst and more deaths follow.

Bessie puzzles over what is happening and realises she doesn't know her friends as well as she thought. What's more, she has to deal with events of the past and confront how they might be driving her current ordeal.

It's a good read, it has to be said, and the author has written a number of books of similar ilk, where a common theme is a feeling of being trapped and having a sense of claustrophobia in the murder mystery. They have topped the charts with the New York Times and she is hugely popular in the US.