Pearls are a Spoink's Best Friend (Japanese: バネブーのさがしもの！？ Spoink's Lost Object!?) is the 39th episode of Pokémon: Advanced Challenge.
Continuing their journey to Fortree City, Ash and friends come across a Spoink, who is upset after losing the Pearl it keeps on the top of its head. After Spoink tries to put on a couple of round Pokémon on its head, the Pearl is found. However, during a Team Rocket encounter, they steal the Pearl. After coming across a fair, James is approached by the same Magikarp Salesman who has made his life miserable in the past and offers to trade Feebas for the Pearl. After discovering Feebas evolves into Milotic, Team Rocket agree. However, when they let their new Feebas out to have a swim in a nearby river, they discover the Feebas is just a Magikarp painted with a Feebas' colors, meaning they have been swindled yet again. After Ash and the others find out what happened, they have to get Spoink's Pearl back by finding the Magikarp Salesman before Team Rocket do.
Team Rocket is fighting in a phone booth for who gets to call. Giovanni calls them to hear the news of the base. Team Rocket claims they made it, but it is destroyed. Giovanni is frustrated since they report no success in Hoenn region and claims he should send Butch and Cassidy to do the work. Team Rocket claims there is no need for them, as they will finish the job. Giovanni hopes for some better news next time and before he logs off, Persian taunts them. When the video call is logged off, Meowth gets furious over Persian, since it annoyed him. Just as they decide to do something bigger and better, Jessie's Wobbuffet comes out of its Poké Ball, which crashes the telephone booth. The next day, Brock is cooking breakfast while Ash, May and Max brush their teeth. As the heroes have breakfast, they hear something from a bush, so Skitty goes in and returns to May, looking scared. The Pokémon, Spoink comes from the bush, but it is missing a pearl on its head and that makes it very tired.
Torkoal cries for Spoink's loss, so the heroes decide to help Spoink find the pearl. Spoink and the gang go to search for the pearl. Spoink demonstrates it slept at a tree and fell over, causing the pearl to fall off the cliff and Spoink lost it since then. After descending down, Brock sends Mudkip to help in the search. Spoink found its pearl and uses Psychic to put on its head. However, it is actually Igglybuff. A girl appears and sees her Igglybuff, bot Spoink goes away, making the girl cry. Brock and Max stop it in time, since Spoink should return Igglybuff to its trainer. Next, they encounter a Voltorb and Spoink uses Psychic to put on its head. The heroes go to give it to a boy, who arrived, but are electrocuted by Voltorb. Next, they encounter Electrode, so Spoink (seeing it is round) puts on its head, but Electrode uses Explosion. The heroes gives up, but Mudkip spots a round object, which is actually its own pearl. Spoink puts on its head and hops away happy, which makes Torkoal cry, happy everything is back to normal.
Just then, everyone falls into a hole, causing Team Rocket to appear soon after. Team Rocket says they are new and Jessie cuts a rope, so everyone is pulled up inside a net. Ash sends Corphish, who cuts the net. During their fall, Spoink loses its pearl, with Meowth catching it. Unhappy, Jessie sends Seviper and James his Cacnea, but the latter hugs the former. Corphish attacks with BubbleBeam, but Seviper dodges and goes to Wrap Corphish, but the latter avoids it. Cacnea attacks with Pin Missile, but Corphish deflects the attack using Harden, then attacks with Crabhammer, knocking Seviper and Cacnea out onto Team Rocket. Corphish uses BubbleBeam and Mudkip with Water Gun, blasting Team Rocket off. Max sees Spoink without its pearl, realizing Team Rocket took it. After falling down, Team Rocket got the pearl, making Jessie think it would lift up her social status. Meowth thinks it would look good on boss' ring, but realizing it would be quite heavy for a ring, he claims the boss can wear it on his crown. The heroes appear, but Team Rocket runs away and recalled their Pokémon. They disappear into a crowd of people, as a carnival is being held.
They search for the pearl and Spoink sees a juggler, so it takes one of the balls, but soon returns it after the gang intervenes. Same goes with a fortune teller and her crystal ball, so May asks Spoink to calm down. Team Rocket wanders around, seeing a lot of entertainers. James catches a Feebas and sees a man, the same man who sold a Magikarp to him. He offers them the Feebas, but Jessie remembers her encounter with the Feebas, who grabbed her hair. The salesman shows them a video where Feebas evolves into Milotic. James and Meowth are still not convinced, but the salesman tells them that he has family back home and he changed his ways of trading, which amuses Jessie to get one. Since they have no money, the Magikarp salesman takes the Spoink pearl for the Feebas. Team Rocket puts the Feebas to swim in the water, however, its color fades, revealing to be a Magikarp. Jessie goes mad for such a rotten deal, though James claims things could be worse. Just then, the heroes appear.
The heroes demand the pearl, but Team Rocket explains what happened to it. Max laughs, claiming they aren't quite bright, though Meowth defends himself, stating they would've done the same. Team Rocket runs off to find the salesman, as do the heroes. The gang finds the salesman, so Brock and Ash have an idea. Brock hides and his Mudkip uses Water Gun on Feebas, revealing it to be a Magikarp. The salesman tries to get away, but is intercepted by Brock, as the heroes demand the Spoink pearl. After a smoke bomb is thrown, Team Rocket appears as well, wanting the pearl back. Spoink uses Psychic, placing the Magikarp on its head, which displeases the heroes, since Magikarp is not even round. However, Spoink falls down, being very exhausted without its pearl. Ash and the salesman fight for the bag, which gets ripped and the pearl is thrown into Meowth's hands. Jessie sends Dustox to protect the pearl, while Ash sends Torkoal to intercept.
Dustox attacks with Poison Sting, but fails due to Torkoal's Iron Defense. Torkoal uses Flamethrower, hurting Dustox. James sends Cacnea, who, once again hugs James before using Needle Arm. Torkoal repeats Iron Defense, negating Cacnea's Needle Arm. Torkoal attacks with Body Slam, knocking Cacnea out. Dustox attacks with Psybeam, which hits Torkoal. Mudkip uses Water Gun, knocking Dustox out. During the battle, the Magikarp salesman runs off. Cacnea attacks with Needle Arm, but misses Torkoal, who attacks with Overheat, knocking Cacnea onto Meowth, who drops the pearl. Max puts the pearl on Spoink's head, which recovers the latter to full health. Spoink uses Confuse Ray, confusing Cacnea and Dustox, then blasts Team Rocket off with Psychic.
The heroes comment Spoink for its powerful attacks. Max notices the salesman's gone, but the heroes are glad Spoink is at least better now. The heroes leaves, waving goodbye to Spoink.
- Featured Pokémon: Electabuzz, Steelix, Cacnea, Shiftry.
- In the beginning of the episode, a classic Pokémon identification can be seen. In this episode, it is a Slowbro.
- The dub title is a play off the song "Diamonds are a Girl's Best Friend."
- This episode is featured on the Volume 7: Psychic copy of Pokémon Elements.
- On Pokémon.com, the title of this episode is erroneously spelled as "Pearl's Are a Spoink's Best Friend".
- This is the fifth time the Magikarp salesman has appeared in the anime, and the second time Team Rocket has acquired a Magikarp from him.
In a brief moment, Spoink's nose is shown on its back.
The footage of James looking up a Spoink TCG card is cut in the dub. Cards seen included Spoink, Seviper, Skitty, Lotad, and Mudkip.