A young woman is found dead on the outskirts of St Petersburg on a freezing January morning. There are no signs of injury, and heavy snowfall has buried all trace of an attacker.

Captain Natalya Ivanova's investigation quickly links the victim to the Decembrists, an anti-Putin dissident group whose acts of civil disobedience have caught the eye of the authorities. And Natalya soon realises she is not the only one interested in the case - as government security services wade in and shut down her investigation almost before it has begun.

Before long, state media are spreading smear stories about the dead woman, and Natalya suspects the authorities have something to hide. When a second rebel activist goes missing, she is forced to go undercover to expose the truth. But the stakes are higher than ever before. Not only could her pursuit of the murderer destroy her career, but her family ties to one of the victims threaten to tear her personal life apart.

A captivating, pacy thriller that plunges right into the beating heart of Putin's Russia.