While investigating a possible crime, Shawn stumbles upon one of a pair of criminals, gets shot, and is dumped in the trunk of a car.

The Yin/Yang trilogy comes to a thrilling close as Shawn and Gus race to save a woman kidnapped by Yin. Only this time, they are forced to use Yang's knowledge of Yin to solve the case by allowing her to accompany them on the investigation.

Shawn and Gus are hired by a childhood friend to find a missing camp counselor who disappeared near their old sleep-away campgrounds. Upon their arrival, spooky activity abounds and they must uncover if the dark past of the abandoned camp has come back to life.

Shawn and Gus investigate the death of Leonald Callahan, aka Diddle, a computer cryptologist who was the baritone in Gus’s old college a capella group.

After Gus accidentally tampers with the crime where his boss was killed, Shawn helps him find the real murderer before Gus is arrested.

After eluding capture and disappearing eight years ago, the famed Yin Yang serial killer is back, and he's set his sights on Shawn.

Shawn and Gus spot an art thief whom Lassiter has been trying to arrest for years. So, although they are on a skiing vacation in Canada, they appeal to the local constabulary with mixed results: someone gets axed, another finds himself interrogated and Pierre Despereaux may get away scot-free, once again.

Shawn and Gus return to Vancouver to visit their old nemesis Despereaux in prison at the felon's request, who then uses them to escape and pull one last job before he is extradited to the United States. Only while he is out, he is framed for the murder of a Crown Attorney and now asks the guys for help clearing his name of this most recent – and frankly unseemly – charge.

The episode kicks off with Shawn and Gus receiving a mysterious e-mail inviting them to the annual Cinnamon Festival in Dual Spires, a quirky Northern California town nearly invisible on the map. When they arrive the pair quickly find themselves embroiled in the mysterious death of local high school student Paula Merral. As Shawn and Gus unravel the many secrets of the town, they meet several local residents including town doctor/lawyer/veterinarian Donna Gooden, Sheriff Andrew Jackson, proprietors of the local diner Robert and Michelle Barker, the mysterious Woman with Wood and enigmatic bookish beauty Maudette Hornsby. The pool of suspects proves to be deeper than suspected as Shawn and Gus must work to figure out who killed Paula Merral.

When the hitting coach of the Santa Barbara Seabirds suddenly dies, the team's manager hires Shawn and Gus to go undercover as the new coach and mascot in order to investigate.

After a billionaire murderer pleas insanity at his trial, Shawn and Gus go undercover at a mental hospital in order to prove that the man is, in fact, sane. While at the hospital, Shawn and Gus receive some hostility from one of the nurses.

Juliet's con-man father travels to Santa Barbara to reunite with his daughter, but finds himself slipping back into his criminal past when confronted with a dream con.

After a woman tells the SBPD she witnessed a murder happen in broad daylight, Shawn and Gus are the only ones who believe her, and therefore protect her by hiding her at a remote commune called Box Canyon Ranch, a place whose inhabitants label themselves as progressive intellectuals.

Lassiter hires Shawn and Gus to get to the bottom of strange occurrences at his new condo.

When the daughter of a Chinese Triad family disappears, Shawn and Gus take on the case.

When a woman is found dead with a bottle of pills that are lab trial samples, Lassiter and Gus, who are taking the same tap class, team up to dance their way to catching a murderer

Shawn and Gus work with two retired police officers to solve the murder of a police chief.

Shawn has to face serious competition when a talented criminal profiler named Declan Rand comes to Santa Barbara to help solve the murders of donors on a liver-transplant list.

Shawn stumbles across a dead body at the British consulate's home while working a case to recover a stolen "Star Wars" collector's item. In order to get the police on the case, Shawn claims he had a vision of the murder and puts his reputation as a psychic on the line.

Shawn and Gus help Detective Lassiter enlist the help of Henry and Woody to solve the murder of a real estate executive. Meanwhile, Shawn struggles with a life decision.

Lassiter and Juliet get called to a museum to investigate the disappearance of a 3,000-year-old mummy. Lassiter insists it's just a prank that's not worth his time. He's busy working on another case involving the death of philanthropist William Wyles III. However, the assistant curator insists that something weird is going on, something possibly supernatural that requires special help. Shawn is then brought in on the case, and he declares that the mummy was not stolen, iit walked away on its own.

Shawn and Gus investigate the death of a safety inspector aboard an offshore oil rig. The investigation is complicated by the commander of the coast guard, Barbara Dunlap, Chief Vick's sister.

Shawn and Gus investigate the whereabouts of a mysterious, masked vigilante named The Mantis, who is trying to take down a local drug syndicate called The Caminos. The SBPD is also trying to take down The Camino syndicate, however The Mantis always seems to be one step ahead of everyone's game. Joey McIntyre and Miles Fisher guest star.

The discovery of a washed-up body sparks a debate between Shawn and the police, who both disagree as to how the man died. While Shawn believes that the man was killed by a Tyrannosaurus Rex, the police believe the killer is a little less... extinct.

Shawn and Gus find themselves trying to outwit a bounty hunter when Juliet asks them to find a suspect who escaped from her custody. The problem is, once they find him, Shawn believes his claims of innocence, meaning they not only have to capture him, but prove he's been set up.