This past week, Psych fans were in for a treat when a third movie was announced. Psych 3: This Is Gus is the third in the made-for-TV movie series that continues the story of the popular show that ended its run in 2014. The series follows Shawn Spencer as he pretends to be psychic in order to run a detective agency with best friend Burton "Gus" Gustor.

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This premise allowed the duo to come into contact with a wide variety of colorful characters. While many characters are guaranteed to return such as Lassie and Jules, there are several guest roles that fans hope to see again. There are some that were recurring characters on the show, and there are a few that have only been featured in one episode and deserve to make a comeback.

Ewan O'Hara

Julian and Ewan looking at something

While only in one episode, Juliet's brother Ewan, played by John Cena, quickly became a fan favorite. The character is shrouded in mystery, making him fit perfectly with the zaniness the show offers. Ewan instantly took a liking to Shawn, and Shawn likewise became fascinated by Ewan. Ewan shows to care immensely for his sister, and is shown to do what he thinks is right regardless of the consequences.

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Ewan made a cameo appearance at the end of the first movie, but fans want to see Shawn and Gus join him on another adventure, and a guest role in a movie is perfect for this. With a bigger budget, the exploits of Ewan could take Psych on a globetrotting adventure that fans are begging for.

Frank O'Hara

Frank points at his head with his finger

William Shatner played Juliet's estranged father Frank in two episodes of the series. Frank is a con man who manages to trick the observant Shawn on more than one occasion. While being a criminal, Frank shows he has a hidden heart of gold and wants nothing but the best for his daughter.

Frank's return could show more of the relationship between father and daughter, and could even show the relationship with his son if Ewan were to return. While getting himself into trouble, Frank has proven to be one of the smarter characters on the show, so seeing more of his intelligence against someone like Despereaux could be interesting.

Jack Spencer

Jack Spencer leaning against a wall

Shawn's Uncle Jack is an example of a character who only made one appearance. The episode he was featured in has been regarded as one of the best, yet he never returned. Jack is one in a long line of con men in the show. What makes him different, is he is essentially a treasure hunter.

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While older brother Henry sees him as a whack job who is throwing his life away, Shawn has looked up to his uncle and seems to have inherited his sense of adventure. Similar to Ewan, Jack's appearance in a movie could provide a large-scale adventure the show couldn't contain.

Abigail Lytar

Abigail Lytar and Shawn Spencer talk over dinner on a date in Psych

While always destined to be with Juliet, Shawn has had several love interests over the run of the series. The one that seems the closest to working out is would be high school sweetheart, Abigail. After being reunited with her at a high school reunion, Shawn tries to make things work with her and for a while, it seems like everything is running smoothly.

After being kidnapped by a serial killer, however, Abigail realizes a life with Shawn is far too dangerous and they mutually decide to split. While married to Jules, Abigail could still have a place in the third Psych movie. Fans would love to see her return, and Shawn would appreciate seeing his old friend again.

 Marlowe Lassiter

Lassiter with his arm around Marlowe's shoulders

From the beginning of the series, Detective Carlton Lassiter seems to not have the best luck when it comes to women. A chance encounter at a bar has him meet Marlowe, and it is love at first sight. Lassie eventually marries and has a child with Marlowe, and he becomes a better man because of it. Marlowe was absent in the first Psych movie and had a brief cameo appearance in Psych 2: Lassie Come Home.

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Fans want her to return in a bigger capacity in the third film. Seeing married life with the Lassiter's seems like a fun time, and everyone wants to see Carlton's daughter. Marlowe is a fan favorite, and it would be a shame to not have her return.

Dennis Gogolack

Dennis wielding a pair of nunchucks

One of the most memorable one-shot guest stars is Dennis played by teen heartthrob and Scooby-Doo star, Freddie Prinze Jr. Dennis is a childhood friend of Shawn and Gus, and seems to be a jock and has grown up from his childish shenanigans. This couldn't be further from the truth, as Dennis shows he is a closet nerd and has a hidden command center in his house.

Dennis acts as if he has known the Psych duo for years, and it is nice to see a third party join the lifelong friends. Dennis was only in one episode and is overdue for a return to Santa Barbara.

Betsy Brannigan

Betsy blows the smoke out of a gun's muzzle

When Carlton was promoted to chief, he naturally needed to find a new head detective. Juliet was the obvious first choice, but she had moved with Vick to San Fransico. he instead finds Betsy Brannigan who while at first seems to be everything Lassie hates, she turns out to be nearly identical to the Detective.

The gun-toting Detective Brannigan was only featured in the last few episodes of the show, so fans weren't able to witness how well she serves as Head Detective. Seeing her return to solve the crime of Psych 3 would be a fine addition to the film, and fans would love seeing her back.

Harris Trout

Harris, Shawn, and Burton talk to someone off camera

Sometimes the best characters are the ones fans love to hate. No guest star better proves this than Harris Trout. Played by Anthony Michael Hall, Trout replaces Karen Vick as chief of the Santa Barbara police department for a brief time.

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Trout demotes Lassiter and refuses to hire Shawn and Gus, making him a despised member of the cast. Besides this, his overanalysis of things and his gruff exterior make him a fun addition to the show. He acts similar to how Lassiter acts at the beginning of the series, so seeing him interact with the now chief Lassiter will be an entertaining experience.

Madeleine Spencer

Madeleine and Shawn embrace and talk

Shawn's mother made her appearance in season 3 and made several guest appearances since then. She appeared as the voice of reason between Shawn and Henry and has proven to be a valued member of the Spencer family. Madeleine is absent from the previous two Psych movies, and fans want to see her return in the third outing.

Shawn's mother fits right in with the powerful women of the series, and it is a shame she has yet to make a comeback. It is always interesting to see what Henry is up to in between movies, so adding Madeleine into the mix would be a fun addition.

Pierre Desperaux

Cary Elwes as Pierre Desperaux in Psych

One of the guest stars who made the most appearances is Pierre Desperaux. The famous art thief has constantly proven to be able to outsmart any of the characters and has become one of Shawn's biggest idols. Pierre has escaped prison on several occasions, even a few times in one episode, and proves to be one of the fan-favorite characters.

When fans last saw Desperaux, he revealed that he was never an art thief, and instead a government agent going undercover as such. The episode leaves it ambiguous as to if he is telling a truth or if it is another trick, and his return would prove whether or not he is yet again lying. Desperaux's adventures were the highlight of the show, and his inclusion in the movie would be a welcome plot point.

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