Daniel Jackson discovers that in 1945, a brilliant young professor went through the Stargate, never to return. Together with his fiancee, Catherine Langford, SG-1 discovers the now aged Ernest Littlefield trapped in a decaying castle. With Daniel captivated by Ernest's amazing discoveries, the others race against time to get them all home.
1.12 - Bloodlines
With the proviso that they bring back a Goa'uld larva for study, Teal'c returns with the SG-1 team to Chulak to stop the Goa'uld from enslaving his son Ry'ac. After a difficult reunion with Drey'auc, the wife he abandoned, Teal'c discovers that his son is dying. He needs the healing properties of a larval Goa'uld and the only one available is Teal'c's own.