The hunt is on for a serial killer in a thrilling festive crime novel.

It looks like a regular advent calendar.

Until DC Becky Greene starts opening doors...and discovers a crime scene behind almost every one.

The police hope it's a prank. Because if it isn't, a murderer has just surfaced - someone who's been killing for twenty years.

But why now? And why has he sent it to this police station?

As the country relaxes into festive cheer, Greene and DS Eddie Carmine must race against time to catch the killer. Because there are four doors left, and four murders will fill them...

It's shaping up to be a deadly little Christmas.