Mary Lightly

This is a list of characters in the USA Network original comedy-drama TV series, Psych. The principal cast of the series has remained the same throughout the series. However, various recurring characters have appeared over the course of the show's run.

Young Shawn (portrayed by Liam James and Skyler Gisondo in the majority of appearances) is the younger version of Shawn Spencer. He is almost always shown learning life lessons from his father, usually tying into the main events of the episode. The character usually appears in flashbacks to the late 80s or early 90s. Young Shawn first appeared in the pilot episode, and has appeared in nearly every episode since.

In "The Polarizing Express" (5.14), Young Shawn appears in adult Shawn's dream in 2010. The character makes light of the rotating actors in the role when Tony Cox comments that Shawn and his younger self look nothing alike. Young Shawn (portrayed by Skyler Gisondo) replies, "Well, we changed!" Then, looking at adult Shawn he says, "Sometimes from week to week, huh?," which adult Shawn confirms.

In "And Down the Stretch Comes Murder" (2.05), Young Shawn occurs in multiple flashbacks in which Shawn tries to find the culprit that shot a spit ball at the teachers head, ending in getting Jimmy (Bully) kicked out of school. Jimmy, now a horse jockey, returns in the beginning of the episode, to hire Psych to talk to his horse.

Young Gus (portrayed by Carlos McCullers II in the majority of appearances) is the younger version of Gus. He almost always appears with Young Shawn, occasionally learning life lessons from Henry as well. The character always appears in flashbacks to the late 80s or early 90s. Young Gus first appeared in "Spellingg Bee" (1.02) and has appeared in many episodes since.

Officer (Junior Detective (season 8)) Buzz McNab (Sage Brocklebank) is a member of the SBPD, who occasionally works with Detectives Lassiter and O'Hara, as well as Shawn and Gus. McNab is a naive, lovable cop who is always eager to please Lassiter, even though Lassiter doesn't always treat him well. He first appeared in the pilot episode, and has been shown occasionally.

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