The Replicators threaten to overwhelm the galaxy, taking out the Goa'uld and then Earth. While Sam and Thor work to develop a weapon, Teal'c and Bra'tac lead the rebel Jaffa in taking a major temple and Jack and Jacob are forced to make an alliance with Ba'al.

While Daniel finds himself in a mysterious diner suspended between death and ascension, Jacob's fate takes an unexpected turn, Jack and Sam consider their romantic lives, and Anubis unleashes his plan for galactic destruction.