Russian-born Nikolai Luzhin is a driver for one of London's most notorious organized crime families of Eastern European origin. His carefully maintained existence is jarred once he crosses paths at Christmastime with Anna Khitrova, a midwife at a North London hospital. Anna is deeply affected by the death of a teenager while giving birth to a baby, and she resolves to try and trace the baby's lineage and relatives. The girl has a personal diary, but it is written in Russian. Anna accidentally unleashes the full fury of the crime family, and Nikolai unexpectedly finds his loyalties divided. Hanging in the balance is a harrowing chain of murder, deceit, and retribution.