Chloe has decided on her school research project: Pokémon fossils. Ash and Goh accompany her to an excavation site, with Goh becoming excited at the thought of possibly catching a Fossil-type Pokémon, but Team Rocket follows them with the same idea in mind. Goh finds a Secret Amber, which that night (after Team Rocket breaks into the Restoration Room and meddles with the machinery) is revived into an Aerodactyl, which escapes! But while Goh is determined to catch the new Aerodactyl, Ash must battle Team Rocket on his own. (Source: Wikipedia)