In 1868 London, the Assassin Brotherhood has been nearly wiped out and the city lies firmly under Templar control. Crawford Starrick, a powerful industrialist and crime lord, commands a network of allies embedded throughout London's institutions. Twin Assassins Jacob and Evie Frye travel from Crawley to the capital to dismantle Starrick's grip on the city. Jacob works to undermine Templar power by eliminating Starrick's lieutenants across London's boroughs, while Evie pursues a Piece of Eden known as the Shroud, racing Templar occultist Lucy Thorne to locate it first. Aided by historical figures such as Alexander Graham Bell, Charles Darwin, and Charles Dickens, the twins build their own street gang, the Rooks, and wage a campaign to liberate London district by district. As the siblings clash over their differing approaches, they must ultimately unite before Starrick can seize the Shroud and consolidate his power over Britain.