At first, Stinky Pete was friendly and acted like a grandfather figure and a mentor. However, he soon snapped and turned out to be evil, having grown bitter at the fact that he spent his life on a dime-store shelf and was never sold.
The Prospector doll has never been opened and is still "mint in the box," making him sought after by collectors. He always carries a pick around like a real prospector, and had lived his entire life in a box. Thus, he was greatly valued for still being in mint condition. He spends much time in storage with Bullseye and Jessie, and eventually meets Woody after Al stole him. Stinky Pete is excited, as this meant that he and the gang could finally reside in the Konishi Toy Museum without the fear of destruction by kids. Unfortunately, Woody still had an owner, prompting Stinky Pete to stop him from returning to Andy at any cost. When Woody tries to retrieve his severed arm from Al, Stinky Pete, unnoticed by Woody, leaves his box and turns on the T.V., waking up Al. He places the remote in front of Jessie so that he couldn't be blamed for the incident. After getting repaired, Woody decides to leave the gang for home, but Stinky Pete convinces him make amends with Jessie first. After hearing Jessie's sad story of how she was abandoned by her former owner Emily, and learning from Stinky Pete that Andy would eventually grow up as well, Woody decides to stick with the gang to join them in the museum.
However, Buzz Lightyear and his friends arrive at the apartment room to save Woody from being sold. Buzz leaves Woody to contemplate his decision, saying that he would never be loved again if he spent eternity behind glass. Stinky Pete tries to commend Woody after Buzz leaves the room, but is unable to cheer up Woody, who was disappointed of what he had done to Buzz. As Stinky Pete watches Woody, Woody comes to realize his mistake and declares to Buzz that he would come back with him and the others, making Stinky Pete determined to stop Woody from escaping. While Woody tells an uncertain Jessie and an eager Bullseye that he would take them home to Andy, Stinky Pete decides to take the matter into his own hands as he exits his box, traps Woody and the others by shutting the grate leading to an air vent, and reveals that he was the one who turned on the T.V. the night before (to sabotage Woody's escape). He then swears that Woody and the gang are to go to Japan with him, where they would spend eternity with him in a protected exhibit, away from kids' reach. Woody and Jessie try to stand up to Stinky Pete, only to learn that the Prospector was never sold to anyone after he had spent a lifetime on a dime-store shelf, and was therefore resentful. The Prospector declares that the museum is his only chance of finally becoming appreciated, and he would have no "hand-me-down cowboy doll" to foil his plans anymore. When Woody yells for Buzz's help, Stinky Pete discourages Woody by making fun of Buzz Lightyear's name and revealing how much he hated those upstart space toys. Al then arrives and packs his Roundup collection, including Woody, into his case and heads out of his penthouse.
At Tri-County International Airport, Stinky Pete fights every one of Buzz's attempts to save Woody including hitting him off the rail, but Woody fights back for harming his friend. Stinky Pete reopens an old tear on Woody's arm and offers him a choice of going to Japan together or in pieces, assuring that Woody would be fixed again in Japan. He orders Woody to get back into the case, to which Woody refuses, prompting Stinky Pete to raise his pick, threatening to tear him apart. Suddenly, Stinky Pete gets stunned by flash cameras that Buzz and the other toys had acquired from another luggage. After Buzz grabs him, Stinky Pete warns the toys that they would be tortured by children, abandoned, and end up spending eternity rotting in landfill. Then the toys decide, per Woody's decision, to teach Stinky Pete "the true meaning of playtime," and they shove him into an off-screen luggage.
The Prospector ends up in the backpack belonging to a little girl named Amy, who loves to paint the faces of her toys. At that point, Amy decides to give the Prospector a nice makeover. Horrified at this thought, Stinky Pete weeps as he is taken to his new owner's home.
Although this appears to be a bad ending, it is, in a sense, only justice for him. Stinky Pete had endured being ignored by children for decades, and now he was finally being owned by one.
Stinky Pete appears in the game as a meet-and-greet character along the Big Thunder Trail in Frontierland. At one point, he gives the player a fishing rod as a gift. He also asks the player to help track down some rustlers that are supposedly in the area.
From Official Website
"The Prospector was the comic sidekick on "Woody's Roundup," but offstage he is admired as a wise old toy. The Prospector, also called Stinky Pete, is a special toy for another reason - he's in mint condition and has never been taken out of his box!"
- The Prospector was a long-time member of the Roundup Gang on TV, and was often the butt of many humiliating jokes including having the sharp end of his pickaxe stuck in his bottom.
- He is the second Pixar villain to be physically fought. The first was Hopper, who was fought by the ants and circus bugs.
- Despite being a protagonist on the TV show, in reality, the Prospector was an antagonist as he tried many times to convince Woody to go to Japan with them and hurt some of Woody's friends.
- Stinky Pete was marked by his severe hatred for "space toys", whom he had blamed for causing the cancellation of the show, which ran on TV until the launch of Sputnik, which led to children's subsequent loss of interest in cowboy toys.
- After Toy Story 2 was released, there were interviews with all the characters on the website, including Stinky Pete, who stated that he had grown accustomed to having Amy decorate him, and he liked it, having reformed with a change of heart.
- Although Stinky Pete doesn't appear in Toy Story 3, he appeared in Toy Story 3: The Video Game as a minor character (this time more like the Woody's Roundup version). Kelsey Grammer didn't reprise the role.
- Stinky Pete predicted some of the events of Toy Story 3.
- In an outtake from Toy Story 2, Stinky Pete was talking to the Barbie twins about getting them a part in Toy Story 3. Since this was non-canon, it turns out it wasn't real, as only one Barbie appeared in the third film.
- Before Buzz, Woody and the gang stuffed him into Amy's backpack, he said that the toys would end up in a landfill, and they did.
- In Toy Story 2, Prospector asked Woody if he thought that Andy was going to take him to college or on his honeymoon, as it was unlikely an adult would do so. While in Toy Story 3, his prediction on that turned out to be true, with Andy ultimately handing Woody, along with his other toys (including Jessie and Bullseye), over to a girl named Bonnie Anderson. However, it should be noted that Andy was indeed initially planning on taking Woody with him to college, therefore defying the Prospector's expectations.
- There is a Toy Story 3 poster where Stinky Pete is leaning on a 3, possibly hinting that Stinky Pete was originally going to be in the third film.
- According to his box, the Prospector said 9 phrases, which probably went for the rest of the gang as well (except Bullseye). Some of them included: "There's Gold in them ther Hills", "Help! I think I'm stuck", "Aw...Shucks-A-Boo" and "Oh Boy!...Beans for Dinner."
- Despite the fact that he is neither one of Andy's toys nor one of Bonnie's toys, Stinky Pete makes a cameo in Toy Story Mania!. Again, like the Toy Story 3 video game, Grammer did not reprise his role.