The plot is set in a fictional history of real-world events and follows the centuries-old struggle between the Assassins, who fight for peace with free will, and the Templars, who desire peace through control. The framing story is set in the 21st century and features the series protagonist Desmond Miles who, after falling into a coma during the events of Brotherhood, must relive the memories of his ancestors through the Animus device in order to awaken and find a way to avert the 2012 apocalypse. The main story follows an aged Ezio Auditore da Firenze (the protagonist of the trilogy) as he travels to Constantinople in 1511 to find five keys needed to unlock a vault built three centuries ago by Altaïr Ibn-LaʼAhad (the protagonist of the first film). While searching for the keys, Ezio becomes caught in a feud between the Ottomans and the Byzantines, and discovers that the Templars are also attempting to unlock Altaïr's vault and its secrets.
