*On PY3-948, the SG-1 team finds the bodies of the Linvris, a league of lesser Goa'uld. The cause of death is unknown, but after returning to Earth Daniel begins experiencing hallucinations and is diagnosed with schizophrenia. Soon afterward Teal'c collapses, and the cause is traced to an artifact from the planet, a tablet containing tiny Goa'uld killing parasites created by Ma'chello. However, when the parasites are examined in the lab, they infect O'Neill, Carter, and Fraiser as well. A unique protein marker in Carter provides immunity, but she must find a way to transfer this immunity to others. *Source: Back of card