LOGLINE: Shawn and Gus step into a real life urban legend, as they investigate a death suspiciously like the tale of "Scary Sherry," who met her untimely end at the now haunted Wispy Sunny Pines mental institution.
On Halloween night in 1985, Shawn and Gus witness a troubled girl throw herself from her window at the Wispy Sunny Pines mental institution. From that moment on, "Scary Sherry" has haunted the halls of the now abandoned facility where we find a girl, Doreen Harthan, being chased by what appears to be her ghost through the halls of Wispy Sunny Pines, falling through the same window to her death below.
In the Psych office, Juliet comes to Shawn and Gus for help. She is undercover as Mary Lou Baumgartner, national alumni vice parliamentarian of the Beta Kappa Theta sorority, of which Doreen was a pledge. The going theory is that Doreen killed herself in a copycat of Sherry's original suicide but Juliet thinks there is more to the story. She's sure Doreen's sorority sisters know more than they are letting on. She needs a psychic to read the sorority house because the girls think they are being haunted by Doreen's ghost.
Meanwhile, Lassiter has been temporarily reassigned to train a rookie detective from another department. It turns out this rookie, Goochberg, is the oldest rookie in department history. She took the test 14 times before she passed and, despite Lassiter's tutelage and her complete lack of experience, has her own set way of doing things.
At the sorority house, Shawn and Gus are having their best day ever "reading" Betty, Bianca and the rest of the sorority sisters in the middle of their pajama party. As the girls start to describe the creepy unexplainable things that happen there at night, the lights flicker on and off and Doreen's ghost appears screaming "acnaib" outside the window - which sends Shawn and Gus running for their lives.
Gus, the quicker of the two, takes off, leaving Shawn to investigate. He finds evidence that the phenomenon was man-made with speakers and wires. Juliet says anyone could have done it but Alice Bundy, Doreen's best friend from childhood, definitely has a score to settle.