Heading to Iccirus City, Ash & Co. enter Twist Mountain. While traversing the mountain, they start to hear a loud noise and discover an archeologist excavating fossils. Eventually, he finds a fossil for Tirtouga. The archeologist begins to tell a story about how he used to play with some when he was a child, but in the process of telling the story, Team Rocket make an appearance, with desires not just upon the fossil...

On their way to Iccirus City, Ash & Co. bump into a trainer who maintains he has the strongest Pokémon. It turns out that this trainer is the original trainer of Ash's Tepig, who discarded Tepig, thinking it was weak and not worth training. Ash gets angered by this attitude and decides to challenge him using Tepig in a Double Battle to prove him wrong. Will Tepig be able to show his previous trainer how strong it is, or will that trainer turn out to be right?