A Stealthy Challenge

The episode begins when Ash trains his Froakie and Pikachu, who use Water Pulse and Thunderbolt. As Ash's friends admire his spirit, Bonnie and Dedenne notices something floating in the river. Ash sees that it's his friend, Sanpei, and immediately dives to save him. Soon Sanpei wakes up while Clemont feeds his Greninja a berry to cure its poisoning. Sanpei thanks them, while the heroes notice Greninja evolved from his Frogadier. They are curious why Greninja was poisoned, but soon hear a voice. An enemy ninja and his Barbaracle appear, who attacked Sanpei and wants their secret document.

Barbaracle uses Razor Shell, but is countered by Froakie's Cut. Pikachu uses Thunderbolt on Barbaracle, who is not hurt. Team Rocket observes and focus on taking the advantage of this situation by capturing Pikachu. Clemont proposes they need to get away, so Sanpei uses his ninja power of leaf concealment to escape from the enemy ninja. Later, the heroes are safe, but Clemont remembers the enemy ninja mentioned a secret document. Sanpei replies Saizo, a his instructor, ordered him to deliver this document to a certain mansion before sunset. He accepted the task and went with Greninja, but was ambushed by that enemy ninja.

His Barbaracle used Razor Shell, so Greninja countered it with Smokescreen. The enemy ninja blew the wind to gust the Smokescreen away, so Greninja used Quick Attack. Barbaracle took the hit and poisoned Greninja with Poison Jab and hit it again with Razor Shell. Greninja was thrown away and Sanpei tried to save it, but fell in the river. Sanpei does not know why the enemy ninja wants his document, but has to deliver it. The heroes decide to help Sanpei, as they are his friends. Clemont sees they need a plan first. His glasses shine, as he presents a machine which will leave footprints over the forest, for that should distract the enemy ninja looking for them as they go onwards.

Team Rocket try to find the twerps. They notice footprints and hear them approaching. Jessie and James start their motto, but are interrupted by Meowth, who points out it is a machine. Jessie is angry and kicks the machine, causing it to explode and they all got covered in soot. Sanpei shows the map, where the route is being noted. However, he knows they won't make it if they took the route. He remembers there is a shortcut, but it is quite dangerous, but Ash replies they will take it, for nothing should scare them. They take a narrow path. Clemont takes a step, but the wooden support breaks, causing him and Serena to fall. Greninja uses its tongue and Froakie its Frubbles to save them and pull them up.

They climb up and Sanpei points at a tunnel, which should lead them to the other side, though they are being watched. The heroes take the tunnel, which goes downhill. Suddenly, Golbat wake up and use Air Slash to hit the heroes. Greninja uses Smokescreen to distract Golbat as the heroes and Sanpei escape. However, the Golbat use Air Slash on Clemont. Ash and Sanpei come out and see the mansion Saizo spoke of. However, they see their friends are gone, while Barbaracle and the enemy ninja appear. Sanpei orders Ash to escape, but he responds he will stay by his side and defeat the enemy ninja, then search for others.

Froakie and Greninja use Double Team, surrounding Barbaracle. Froakie uses Water Pulse and Greninja Water Shuriken, though Barbaracle dodges, causing Greninja and Froakie to hit each other. Pikachu uses Electro Ball, but is countered by Razor Shell. Suddenly, a net is released, but Pikachu dodges, as Team Rocket has arrived. Meowth releases another net, but the enemy ninja and Barbaracle cut it, as they were the ones that want Sanpei and Ash. Wobbuffet and Meowth charge to attack, but are hit by Barbaracle's Razor Shell. With Froakie and Greninja's Water Pulse and Water Shuriken, Team Rocket blasts off.

The enemy ninja continues his battle, as Barbaracle uses Poison Jab, but Greninja avoids it. Froakie uses Double Team, followed with Cut, along with Pikachu's Iron Tail. Barbaracle smudges them all using Mud-Slap, negating the attacks. Barbaracle uses Poison Jab, intending on finishing Greninja and Pikachu. Froakie struggles in the rocks and sees this. While causeing a major blast, Froakie evolves into a Frogadier and takes the hit. Barbaracle uses Razor Shell, which Frogadier counters with Cut. Barbaracle uses Poison Jab, though gets attacked by Frogadier's Aerial Ace. The enemy ninja uses the leaf concealment power and escapes, telling them they can find their friends at the mansion. Sanpei knows even if it is a trap, they still have to continue.

They come to the mansion and are shocked to see Serena, Clemont and Bonnie. The enemy ninja appears and takes his disguise, so Sanpei recognizes him as Saizo. Saizo explains he was testing Sanpei, while he saved their friends from the Golbat. Saizo is pleased, for Sanpei acted quickly and smart in many situations. Serena sees Froakie evolved, while Bonnie wishes Frogadier could change back so she can see it evolving as Clemont states that evolving doesn't work that way. Ash proposes a battle against Sanpei, who accepts, as their Frogadier and Greninja fight.