Dorothy and her husband are invited by friends to Branston Abbey for a country house weekend. Thirteen other guests she hardly knows. A rambling Tudor mansion, full of secrets. What could possibly go wrong?

A lovely dinner is just getting into its stride when a huge storm rolls in. The lights go out. And with no electricity or phone service, and cut off by flood waters, Dorothy feels like she's stuck in an Agatha Christie mystery. A guest is found unconscious, another disappears, and there's a horrifying discovery in one of the bedrooms.

They are being picked off one by one. Can amateur sleuth Dorothy discover the culprit before anyone else dies?