Pokémon 4Ever

Forty years in the past, a boy named Sammy rescues Celebi from a Pokémon Hunter. Celebi's time-traveling power sends both of them into the future, where Ash, Misty, and Brock help the injured Pokémon reach a healing lake. Their efforts are threatened by the Iron Masked Marauder, a Team Rocket member intent on capturing Celebi.