Pierre Despereaux, a.k.a Royston Cornwallis Staley, is an English, elegant, sophisticated, James Bondesque art thief. He is known for getting in and out of any place before anyone notices, usually taking several priceless art pieces with him. He has a flair for elaborate plans, elegance, and colorful vernacular. He manages to evade the police all over the world and as a result, is wanted by Interpol. Despereaux heists worldwide which convinces Shawn that he is the "Greatest Thief That Ever Lived". He is portrayed by Cary Elwes.
Shawn first meets Despereaux in "Extradition: British Columbia" when he is on a ski vacation in Canada and recognizes his face from Lassiter's wall of criminals in his apartment. Shawn shouts his name and he flees, leading to a high-speed ski chase scene in which it is shown that Despereaux is a much better skier than Shawn and Gus. Despereaux then proceeds to "steal" an expensive baroque necklace, leaving a still-burning expensive blonde cigarette in the owner's ashtray, his calling card. Shawn realizes that Despereaux is still in the building and chases him to the roof, but Despereaux makes an impressive base jump from the building and leaves Shawn looking foolish when the RCMP, Lassiter, and Juliet get to the roof and find Shawn and Gus alone. Despereaux finds out about a restaurant where Shawn has dinner reservations and surprises him there, and taunts him by writing out his plans for the rest of his stay in Canada, saying he's never been anywhere close to being caught and he wants to make it more interesting for himself, before promptly slipping away once more.
Following Despereaux's list, Shawn seeks out the Manet he is planning to steal, but is foiled once again when they arrive to find that the Manet has already been stolen. Endeavoring to get one step ahead of Despereaux, Shawn figures out where his hotel room is and sneaks in, knowing that Despereaux uses the names of famous artists for aliases and seeing a room booked to Edgar Degas. Shawn goes to rifle through Despereaux's things and then plans to wait for him dramatically in the dark, but Despereaux already has the drop on him and is doing what Shawn was planning to do; as soon as Shawn finishes describing his plan to Gus on the phone, Despereaux flips the lamp on dramatically, revealing that he has been sitting there the whole time with a smug smile. Shawn clutches a pillow to himself, afraid Despereaux will shoot him, but Despereaux gives a speech about the depressingly messy state of murders these days, saying he misses when murders were done with "panache" and finesse. He begins packing his things, and Shawn flinches when he grabs a pair of shoes, thinking that it's his gun; Despereaux replies, "no, this is my gun," dramatically flourishing his weapon and pointing it at Shawn, who flinches again. However, Despereaux goes on to explain that Shawn has nothing on him but his word, and furthermore that Shawn is proving quite useful to him, before directing Shawn to leave his room.
Shawn then chases down the final tip on Despereaux's to-do list--that he will treat himself "like a king"--and realizes he is going to steal a crown, but is baffled once more when he finds that the crown was gone long before they got there. This is the final piece in the puzzle for Shawn, though, and he realizes that Despereaux never gets caught because owners in financial distress make it possible for him to steal the items so that they may collect the insurance money, making what he does more insurance fraud than anything else. Shawn then finds the private plane in which Despereaux plans to leave and explains how he figured it all out to him, stating that he is disappointed in Despereaux because he thought he was so cool but he's really just a fraud. Sighing, Despereaux takes out his gun and explains, "It's a pity, but now I'm afraid I'm going to have to hurt you." Naturally, though, the police show up and arrest Despereaux. Grinning as he is taken away, Despereaux turns to Shawn and tells him, "you know, I have often fantasized about escaping prison."
In "Extradition II: The Actual Extradition Part", Shawn and Gus return to Vancouver on the request and tab of Despereaux just before he is to be extradited by Lassiter. Despereaux wants to prove he is the "Greatest Thief That Ever Lived" and escapes from prison to commit an elaborate art theft from the Canadian crown prosecutor's house. But after the job is done he is framed for the death of the crown prosecutor. Shawn eventually discovers it was Despereaux's girlfriend who set him up.
In "Indiana Shawn and the Temple of the Kinda Crappy, Rusty Old Dagger", a valuable shipment of artifacts is stolen from a museum. Shawn needs "professional" help in getting them back. So he calls in Pierre to help them catch the thief who stole the shipment. The thief was actually after a dagger that opens the door to a secret stash of paintings. Over the course of the investigation, Despereaux is forced to fake his own death in order to avoid prison. Then, along with Shawn and Gus, he uncovers the art, revealing many seemingly worthless paintings. He later steals one of these and removes the paint, revealing a Rembrandt underneath. He is now believed by the SBPD to be deceased, though we know this is false, finally making Pierre Despereaux the world class thief that both he and Shawn have always envisioned.
In "Lock, Stock, Some Smoking Barrels and Burton Guster's Goblet of Fire", Despereaux calls Shawn and Gus to England, where he asks Shawn to pose as a getaway driver in a sting to stop a heist. Despereaux claims he is really Interpol agent Royston Staley, and that Despereaux has been his deep cover identity all along, but Gus is still skeptical. Shawn and Gus discover that the entire staff turned over recently at Interpol, so no one has known Staley for long, and no one has ever seen the alleged agent who hired him, so Shawn and Gus suspect that Staley is a fake and Despereaux is up to his old tricks. Their investigation shows that neither Royston Staley nor his mysterious Dutch superior seem to exist, and they are certain their suspicions were confirmed.
When they are called to do the heist, the criminal crew picks up Despereaux as the final member of the crew, though he still claims to be undercover, but Shawn and Gus suspect he just wants the plunder for himself. Just before the heist begins, Shawn recieves a phone call with more information that makes it sound probable that Despereuax is actually Royston Staley as he claims to be, since Interpol would have erased his identity when he went undercover and Royston Staley did exist at one point until his identity was apparently erased by someone at a really high level, and so he feels wrong for having doubted him (and for getting one of the other agents in trouble). When they arrive and realize the heist has already gone down, Shawn and Gus are tied up by the other robbers, who plan to kill them to make it look like a heist gone bad. While they are tied up, they see Despereaux sneaking away with the jewels from the heist, and are convinced that he is an untrustworthy criminal once again.
However, he returns and saves Shawn and Gus in dramatic fashion. Soon Interpol arrives, complete with the mysterious Dutch boss who no one but "Staley" has seen before. However, a royal was killed during the heist, so the Dutch man suspends "Staley", and Shawn and Gus watch as he clears his things out of his office (including the dagger from "Indiana Shawn and the Temple of the Kinda Crappy, Rusty Old Dagger", as "Staley" admits he didn't always color inside the lines), and they finally accept that he is truly Royston Staley, an undercover agent from Interpol.
However, later, Shawn and Gus go to a pub, where they see the man who was supposed to be "Staley"s superior on the streets as a beggar. Gus concludes that this means he had been a fake all along, and Despereaux had infiltrated Interpol, hiring the beggar to play his boss to strengthen his ruse. Shawn suggests that, to the contrary, the Dutch agent could merely be undercover as a beggar in order to uncover some sort of crime ring and Despereaux's story could still be true. Gus replies that it's ridiculous, since beggars don't have crime rings. Shawn then suggests (in a way that is true for the viewer as well) that they can choose what to believe--whether Despereaux is really a master criminal who infiltrated Interpol, or whether he really was Staley the undercover agent, leaving the episode, and the man, with an ever-lingering air of mystery.
- In his last appearance it is revealed that he may or may not be a spy working with Interpol.
- Talented skier.
- Has high appreciation of good art, specifically paintings.