SG-1 tracks down Catherine Langford's fiancee, who took the first Stargate trip in 1945, and discovers an ancient meeting hall that may hold the secrets of the universe itself.

Teal'c returns to Chulak to stop his people from implanting his son with a larval Goa'uld.

With SG-1 trapped on Klorel's ship, it seems that Earth is doomed as the Pyramid Ships prepare to destroy Earth.