When two strangers end up sharing a cabin on the Trans-Siberian Express, an intense friendship develops, one that can only have one ending … a nerve-shattering psychological thriller from bestselling author SJI Holliday

Carrie's best friend has an accident and can no longer make the round-the-world trip they'd planned together, so Carrie decides to go it alone.

Violet is also travelling alone, after splitting up with her boyfriend in Thailand. She is also desperate for a ticket on the Trans-Siberian Express, but there is nothing available.

When the two women meet in a Beijing Hotel, Carrie makes the impulsive decision to invite Violet to take her best friend's place.

Thrown together in a strange country, and the cramped cabin of the train, the women soon form a bond. But as the journey continues, through Mongolia and into Russia, things start to unravel – because one of these women is not who she claims to be…

A tense and twisted psychological thriller about obsession, manipulation and toxic friendships, Violet also reminds us that there's a reason why mother told us not to talk to strangers...