Ash and his friends enter an orienteering competition on Potpourri Island! For this stamp rally challenge, Trainers and their Pokémon compete to be the first to find all the different destinations and stamp their map at each one. The winner gets the Teamwork Medal and boxes of juicy fruit! May lets Max team up with Munchlax and then our heroes—and Team Rocket—split up to enter the race.
Jessie and Meowth decide not to bother with the map, a plan that doesn't work out too well. So they hit upon an even better plan: sabotage the other competitors so James and Mime Jr. can win the grand prize for Team Rocket! The other teams are making progress, but Max isn't doing so great and has to cover it up when he runs into May. To make things worse, Jessie and Meowth cut a bridge while Max and May are still on it. Luckily, Ash and Brock get there just in time for a rescue.
Jessie and Meowth return to the Pokémon Center, where they net our heroes' other Pokémon and all the fruit for the prize. Swellow gets away and warns Ash, who catches up to the criminals at the crime scene. Jessie and Meowth obligingly stop to recite the Team Rocket motto, which gives Ash's friends plenty of time to sneak around them and retrieve everything they stole. After that, it's no contest. Though Jessie and Meowth are defeated once again, their hopes rise when James and Mime Jr. win the competition—except James happily gives away the prize fruit!
Arriving on Potpourri Island, Ash and his friends head straight for the local Pokémon Center where the resident Nurse Joy welcomes them. A group of kids pass by discussing the upcoming Pokémon Orienteering event, which Ash has never heard of before. Nurse Joy explains that it is a cross-country race in which competitors use a map and compass to find their way through unfamiliar territory. Brock quickly interrupts the conversation with his romantic advances toward Nurse Joy, but gets dragged away by Max. Team Rocket, who have been observing the group from up in a tree, decide to participate in the competition, but in disguise. Night falls and everyone gathers at a table in the Pokémon Center to discuss Pokémon Orienteering. Ash decides to participate with Pikachu, while May chooses Eevee, Brock goes with Bonsly and Max borrows May's Munchlax.
The next day, the participants have gathered for the Pokémon Orienteering event. Joy explains the rules of the event as she hands each Trainer and Pokémon team a map and a compass of the surrounding area. Joy then displays the Teamwork Medal that will be presented to the winner of this contest, as well another prize, a vast quantity of fruit. She officially begins the event by saying "Start," and everyone dashes off into the distance and spreads out to the five checkpoints. Meanwhile, Ash and Pikachu are carefully walking across a log located high above a river when a faint wind knocks them both off-balance, but they manage to grasp onto the underside of the log and eventually reach the other side. May begins crossing another part of the river by jumping across lodged rocks but loses her footing and falls into the river with Eevee following. Brock studies his compass as Nurse Joy walks across his path, accompanied by an Oddish. A lovestruck Brock moves toward her, but Bonsly attacks him and sends him blasting off into the sky, leaving Nurse Joy confused.
James and Mime Jr. climb a cliff face to reach the top and arrive at the Moon Rock, which features a stone statue resembling a Lunatone. James, rushes over to the statue and marks his map with the special Lunatone stamp found on a stone slab to show that he has successfully arrived at this checkpoint. Max chases after Munchlax as it dashes off into the distance, greatly motivated by the prospect of the food prize. Jessie and Meowth find themselves lost, after deciding to walk in a straight direction, and standing on a cliff overlooking the ocean. Meanwhile, Ash and Pikachu reach their first checkpoint near a waterfall called Rainbow Falls. Remoraid begin squirting water in arcs over the short path to the slab as Ash goes over to get his map stamped. Brock and Bonsly find another checkpoint near a 300 year old gigantic tree. With one quick swipe of the Pineco stamp, Brock marks his map for completion. Having successfully escaped from the river, May notices two rocky spires rising up from the ocean. She then sees the nearby checkpoint and stamps her map, leaving a Kingler mark.
Jessie and Meowth are now on top of the highest point on the island to locate the checkpoints, but neither of them see any. Frustrated, they give up and agree to help James win instead so he would share the prize. Ash dashes forward and falls into a hidden trap set by Jessie and Meowth, who are no longer in disguise. He soon gets out, however, and reaches his second checkpoint, the Kingler stamp near the two rocky spires. Brock and Bonsly are moving for their next location when they come into contact with a hidden net and are ensnared into a tree. James and Mime Jr. meet Jessie and Meowth, who offer to collaborate with him. James, who righteously desires to win fairly, refuses their help and continues with his Orienteering. After a quick snack break, he and Mime Jr. locate their third stamp, the Kingler one.
May successfully reaches her second checkpoint, the Lunatone stamp. Following a break, May and Eevee take a zipline down to their next checkpoint, but fall in a Team Rocket trap. Max comes upon the river and use a nearby bamboo stick to pole-vault himself and Munchlax across. Just as they land, the ground underneath them collapses as well. May, having escaped the trap, comes upon the Skarmory checkpoint located on a pillar of land between two bridges and stamps her map. Max arrives shortly afterward and sees May, who wishes him luck. Jessie and Meowth appear and cut the bridge ropes with shears, taking the bridge out from under them. May, Max, Eevee, and Munchlax fall, but manage to grab onto the bridge as it lies flat against the cliff. As May, Max, and the Pokémon continue hanging on for life, the remaining ropes begin to weaken. Just as they snap, Brock and Ash appear, catch the collapsing bridge, and lift them to the surface.
The group's Pokémon back at the Pokémon Center are napping together peacefully when a net suddenly ensnares them all. As Meowth sets his eyes on the baby Pokémon left at the Center, Swellow flies away in search of Ash. As Ash and Brock check to see if May and Max are okay, Swellow interrupts with an urgent message. Brock infers that Swellow means to say that there is trouble at the Pokémon Center. When they arrive, Jessie and Meowth, who fills in for James, recite the motto for them. During the full rendition of the motto, May, Max, and Brock calmly reclaim the food prize and free the Pokémon. Team Rocket turn around to see their mistake and so Jessie releases Dustox to battle, who is challenged by Donphan. Dustox Tackles Donphan forcefully, but it retaliates with Take Down sending Dustox back into Jessie and Meowth. Donphan finishes them off with a Hyper Beam that sends the three blasting off again. Having heard their trademark motto, James looks overhead to notice the twinkling light, though continues his efforts to win the Orienteering contest.
As the day concludes, Joy announces "Jameson" and Mime Jr. as the winners of the contest and presents them with the Teamwork Medal. The crowd cheers, but Joy asks James if he would consider giving the food prize to Ash and his friends for defending the Pokémon Center. He agrees with no hesitation, shocking Jessie and Meowth, who had been helping him just to get the food in the first place. The day concludes with May more enthusiastic than ever for her impending Pokémon Contest, which Nurse Joy informs her will take place in nearby Wisteria Town.