Shawn tracks down Lassiter's car with little difficulty after it's stolen. However, Shawn discovers that there's more to the situation than meets the eye and calls Gus back from vacation to help with the investigation.

Christmas with the Gusters is ruined when Gus' parents' neighbor is killed, a clue leads Lassiter to look at Mr. Guster more closely. Evidence leads the police into arresting Gus' mother too, and Shawn and Gus vow to get them out of jail.

Eugene Franks, arrested by Henry in 1978 for plotting to bomb the SBPD, is released after his conviction is quashed by the D.A. When Shawn is instructed to solve the case, his father insists on helping him; however, the case is not as clear cut as he once thought.

Shawn and Gus investigate a department store Santa who they suspect is up to no good. Meanwhile, Gus' sister flies in for Christmas.

A billionaire hedge fund manager asks Shawn and Gus to find his murderer – a last request Shawn can't resist. So he and Gus step into a world of privilege that's rivaled only by the depths of betrayal it contains.

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.

When Shawn and Gus join Gus’ new girlfriend on a rafting trip, a member of the group goes overboard, but Shawn quickly realizes it was no accident.

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 help a prison guard locate his escaped inmates while on a ferry boat headed to the Channel Islands.

Due to an unlawful entry into a criminals property, Shawn gets suspended from his consultant postition and gets Henry fired from his position at the SBPD at the same time. Shawn has a series of Scrooge type dreams where Tony Cox is his 'spirit guide'.

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.

When the founder of "Right Now", Santa Barbara's oldest at-risk youth program, is shot and almost killed, Shawn, Gus and a few members of Gus's a capella group from college investigate to find the culprit.

A wrongly convicted Southern chef hires Shawn and Gus to find the real thief after the Innocence Project frees him from prison.

After Gus is tasked with taking care of his girlfriend's son Maximus for the day, he jeopardizes their relationship when an innocent trip to the circus turns deadly.

After Shawn and Gus' favorite radio DJ is murdered, they go undercover as on-air personalities to find his killer.

A man enters the morgue and tells Woody that he was framed for the murder of the person lying dead on the slab. When Woody won’t let him take the body, the man pulls a gun on him and holds Woody hostage in order to get what he wants. Shawn, Gus, Lassiter and Juliet try to resolve the situation calmly and carefully, but Interim Chief Trout has a plan of his own.

Gus is determined to solve the murder of a man whose life was strangely similar to his own. Along the way, Gus hits it off with a beautiful Private Investigator named Emanuelle. Meanwhile, Shawn realizes he's been mooching off of Gus, Henry and Juliet, so he tries desperately to make up for it.

Shawn and Gus are bummed to find out the owner of their favorite food truck has been murdered. The two of them go undercover to learn the food truck ropes and find out who the killer is. While working on the case, Marlowe visits them to cure a pregnancy craving and goes into labor at the most inconvenient time.