Season 6 Episode 7 - Shadow Play

A diplomatic party from Kelowna (Quinn's home nation) come to SG Command and want to negotiate. The two other nations on the planet have united against them, and they want military support in return for n'quadria. Jack is leery but Jonas is torn by loyalties to his people. One of the representatives is Dr. Kieran, Jonas' old mentor. When negotiations with the Kelownan government break down, Kieran offers to put them in contact with an underground which has n'quadria. However SG-1 finds out that Kieran is schizophrenic due to exposure to n'quadria radiation and he has hallucinated the entire Kewownan underground. SG-1 gets out with the n'qaudria Kieran has accumulated and they are no longer able to contact the Kelownans. Dr. Kieran is under treatment, but still believes the underground will be rescuing him any minute.