In Assassin's Creed Origins, Bayek is the Medjay who protects the Egyptian city of Siwa.
Bayek is the game's protagonist and one of the last Medjay, an elite protector serving the people of Ptolemaic Egypt. He returns to Siwa at the beginning of the story, where a personal tragedy draws him into a wider struggle against the Order of the Ancients. His investigations eventually help establish the Hidden Ones, the forerunners of the Assassin Brotherhood.
Aya, Bayek's wife, is also central to the plot and becomes an important operative in her own right. Senu is Bayek's eagle companion, while Khemu is his young son. These names are all connected to Bayek's story, but none is the Medjay himself.
Origins is set in the first century BCE, during the reign of Cleopatra VII and the political conflict involving Julius Caesar and Ptolemy XIII. Its Egyptian setting explains the game's emphasis on temples, deserts, tombs, and Nile settlements.