Episode 408 "Temple of Light"

The OSIR launches an investigation prompted by an apparent byonic possession of Starr Moressy, a young star who has returned to acting following a difficult battle with drugs and alcohol. The search begins at a Hollywood retreat called "The Temple" where Starr has returned following her possession experience.
It is run by Griffin who channels an entity named Varik for seekers of the entity's enlightenment, one of whom was Starr. Although Axon is skeptical, Donner and Stone emphatically admit that they believe in Varik's existence.
In the guise of a spiritual seeker, Donner infiltrates the Temple where she discovers that, following Starr's possession experience, Griffin refuses to channel Varik. Instead, he and his colleague, Susan Ashworth try to divert the followers with meditation and healing. But one follower in particular, Freddy Forsythe, persists in pressuring Griffin to bring back Varik.
Tragically, Starr suffers a fatal attack while relaxing by the pool at the Mansion. Curiously, the media reports that the young actress was found dead in her home, the victim of a stroke. Horrified by the events, Griffin tells his followers to keep their minds closed to Varik, but Freddy persists and channels the entity himself. As Varik's spirit takes over Freddy, the young man experiences a phenomenon known as "automatic writing." Realizing that these scribblings are the teachings and prophecies of Varik, he races to Griffin with the papers. Suddenly, Freddy reels as if hit by an unseen force and plummets from a two-story stairwell to his death. Griffin finally tells Donner that he believes Varik is going to kill them all. He feels betrayed by the teacher whom he had trusted completely.
At the lab, Stone finds an unauthorized Varik fan-site that reveals Varik's anti-government teachings and conspiracy theories. Stone and Axon begin to question the real cause of the two deaths and re-examine the autopsy photos of Starr and Freddy looking for clues. This time they see evidence of tiny entrance wounds at the base of the victims' skulls, which indicate that the strokes may have been mechanically induced.
It becomes apparent that someone who wants to ensure that Varik's message doesn't leak out may have killed them. Since Starr and Freddy both died in the Temple, the killer is probably someone working on the inside.

When Donner is warned of the imminent danger, she advises Griffin to let Varik guide him. When Varik starts to speak through Donner, Griffin asks why he has forsaken them. But Varik tells him he meant no harm and that he only wanted his teachings spread. The entity tells Griffin he has been betrayed by someone close to him and Griffin must act fast to save the rest of his followers.