"Man of the People" was from the sixth season. This episode is ridiculous for many reasons.
1) Troi senses something disturbing about an old woman who is the mother to a negotiator. Both the negotiator, a man named Alkar, and his mother were beamed aboard the Enterprise and are on route to a planet to resolve conflict between two factions. The old woman warns Troi to stay away from him or she'll regret it. Troi relays her feelings about the mother to Riker, but agrees to perform a funeral meditation ceremony with Alkar after the old woman dies suddenly. This is before we know how the woman died. Alkar says his mother was old and lived a long life and Troi accepts this! What happened to her empathic abilities? Could she not sense his deception?
2) After the meditation ceremony, Troi exhibits bizarre behaviors and even walks onto Ten Forward in a provocative dress and showing signs of aging with white streaked hair. This is after she seduces an ensign in the middle of a work schedule. Riker finds her with him in her quarters when they were scheduled to do evaluations but doesn't report it to the captain.
3) Data makes the astute observation that "the counselor has altered her appearance." You think? She seduces Riker and scratches him. Next scene, she's in her quarters decades older. Why isn't she in sick bay by now? Yet the creepy Alkar is able to walk in her quarters. She yells at him in the corridor in front of a witness but isn't reported.
4) It's only after she attacks Captain Picard with a knife that she's taken to sick bay by security. Picard then orders an autopsy on the old woman and discovers that the creepy negotiator uses women as "receptacles' for his evil thoughts and desires so he can use his most noble traits to ensure victory in resolving conflicts. Like he couldn't do that without torturing and killing unsuspecting women?
5) And how is it he could accept his deeds as part of a higher purpose if he has diverted his evil self into others? How can he think his actions noble since ridding himself of his worst impulses and negative emotions?
Dr. Crusher finds a way to reduce the neurotransmitters that are causing Deanna's deterioration by stopping her heart and making her dead. She does this out of urgency to save Deanna but they only have 30 minutes before they have to revive her, in which time Alkar can reestablish a link with her.
Alkar attempts to put his bad vibes into a new host but he's stopped before he completes the meditation ceremony with her and he ends up like the Portrait of Dorian Gray and dies.
Good riddance to bad rubbish! Deanna magically turns into her beautiful self in sick bay with no gradual metamorphosis.