The game is set in Ancient Egypt during the Ptolemaic period and recounts the fictional history of real-world events. The player takes on the role of a Medjay named Bayek as he works to protect the people from threats.

In 1868, at the tail end of the Industrial Revolution, with the Assassin Brotherhood all but eradicated, twins Jacob and Evie Frye leave Crawley for London and arrive to find a city controlled by the Templars, with both the Church and the Monarchy losing their power.