Shawn and Gus crash a crime scene of an apparent suicide. One of several in the last few months. This one was an overdose of pills, or so it seems. While in the apartment, though, Shawn notices a few things that might point more toward murder. When no one believes his psychic vision of foul play, he insists he's not leaving until he talks to the witness - the victim's cat.
Even Gus has a hard time believing murder until another body is found. Shawn, Gus and the cat arrive at the second crime scene to find a woman who apparently killed herself by shutting herself in her garage with the car running. Even though a suicide note is written in black eyeliner on the windshield, Shawn still doesn't believe it, and he and the cat point out more inconsistencies with the suicide theory. Lassiter and Juliet are starting to believe.
Shawn and Gus are even more convinced after they discover the latest victim just got her big acting break in a local play. No way she would kill herself after that.
Meanwhile, Officer McNab's wedding is getting closer and he's starting to get nervous about the wedding night. He goes to Lassiter for advice, which needless to say, does not go well. Just then, Shawn, Gus and the cat arrive to tell Interim Chief Vick that the cat doesn't think these are suicides. She tells them she can't reopen the cases based on a cat's intuition.
Since Shawn and Gus can't find any pattern in the killings, they decide to go back to the beginning - the crime scene of the very first victim, David Hiltonbock.
They go to his apartment, where his brother Wes still lives. From Wes they learn that David was a talented musician who was going places. There were no signs of depression. While there, Shawn also "liberates" an old phone bill from the apartment. It turns out that there are several calls to a stress line, including one made the day he died. Gus says that's not really proof of anything. If he were depressed, it would make sense he'd called a stress line. Shawn thinks this could be the link between the victims they've been looking for.