Bio: Cassandra Spender appears as an alien abductee in Patient X where she comes across Mulder and Scully. Mulder at this point is skeptical of her version of events while ironically it is Scully who seems to identify with her. Disabled when we first see her, we find out that her son is an FBI agent Jeffrey Spender who thinks her belief that she had been abducted by aliens is a delusion. We also discover later that she was married to the Cigarette Smoking Man, a marriage that did not end well.
A member of a UFO cult, she also believes that her son was abducted as well when he was a child. Despite being extremely fond of her, her son thinks her views may cause his future prospects harm.
Cassandra though stands firm in her beliefs. She gets taken by a Consortium agent to Ruskin Dam in Pennsylvania where former abductees (including Scully) were gathered. While the rest of the people get killed or left for dead, she is abducted again, lifted into the sky in a beam of light. The only evidence of her abduction is her abandoned wheelchair at the site. Absent for a year, she returns without any need for a wheelchair and any belief in the benevolence of aliens. The Consortium in the time had made her a "perfect hybrid", whose existence was meant to herald the end of the human race.
On her return she confides in Mulder, not her son as he had fallen under the influence of her ex-husband, the CSM. She is later taken to a hangar where she along with most of the Consortium and their families are burnt to death by alien rebels.

• "Oh, Agent Scully, Agent Mulder, you cannot let them find me. You cannot let them have me! " (Two Fathers)