In 1991, a hitman picked up a girl in Vietnam, decided not to kill her, but to make her his protégé, and smuggled her out of the country. 30 years later, Anna and Moody are well-matched partners who, for a hefty fee, "clean up clogs" around the world. Anna keeps a collectible bookstore in London for a living and most of the time leads a quiet, unremarkable life, but one day Moody asks her to track down a man and is soon killed by assassins. After dealing with those sent after her, Anna decides to find those behind it and avenge her mentor's death.