When Finn Wallace, the head of London's most powerful crime family, is assassinated, no one knows who ordered the hit. With rivals everywhere, Finn's impulsive son Sean takes over and puts a stop to all criminal business in London until his father's killer is found. As the city is torn apart by the power struggles of the international gangs that control it, Sean finds the only person he can rely on is Elliot Finch, a low level enforcer with a mysterious interest in the Wallace family.