Pokémon: Mewtwo Returns is a special anime that premiered in winter 2001, produced by OLM.

About the production: the story comes from a video game, there is 1 episode of about 75 minutes and its current status is "finished".

Its main genres are action, adventure, comedy, drama, fantasy and sci-fi, with themes such as Kids, Animals, Male Protagonist and Clone.

On AniList, Pokémon: Mewtwo Returns has an average score of 68%, a good score, and appears on 21,459 users' lists.

The franchise continues in or follows from: Pocket Monsters: Mewtwo no Gyakushuu.

The Team Rocket leader, Giovanni, has found Mewtwo in a remote area of the Johto region. As Giovanni tries to re-capture Mewtwo, Ash and his friends are kidnapped by Domino, a new Team Rocket member, while trying to rescue Pikachu from Jessie and James. The Clone Pokemon are also captured and are then used as bait for Mewtwo. The situation then becomes a battle between the wills of Mewtwo and Giovanni; and Mewtwo also tries to discover if it and the clones have a purpose in life, even though they are products of science. (Source: Anime News Network)

Official synopsis from AniList.