A woman suffering from PTSD receives an experimental treatment to forget the haunting memories of her childhood abduction. When an unforeseen visitor from her past re-enters her life, sinister memories begin to resurface, threatening her sanity.

As Dkpoughq asked -? what is her goal?

As a result of her memories flooding back what is it she must do?

Psychological thrillers can get a bit tricky when dealing with mental conditions, as most of the conflict is internal and hard to visualize with a camera. Does she have anything else she does in the script?

For example, if the unforeseen visitor is the guy who kidnapped her you could specify it. Perhaps she knows he is planning to take another girl, and she is the only one who knows it and knows his MO - it's up to her to stop it from happening again.

"A woman suffering from PTSD receives an experimental treatment to forget the haunting memories of her childhood abduction. When an unforeseen visitor from her past re-enters her life, sinister memories begin to resurface, threatening her sanity."

The beginning is just backstory. It can be shortened and placed into the main action of the logline. Which brings up the questions: What is her goal? What does she try to accomplish during the story? What is the main action of the story? You list it as thriller, what brings the thrills, the suspense? What does this person from her past do, specifically which starts the story? Does he attack her? The last part is also unnecessary, describe the action of the story, the visuals, what we'd see on screen.
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