Ash is back and more determined than ever to be a Pokémon Master! Now he's teamed up with a new friend, Goh, who wants to collect every Pokémon from every region!

Ash and Goh encounter Legendary Pokémon, including Suicune and Eternatus, as they continue their investigation into the Dynamax phenomenon happening in the Galar region. But their biggest challenge involves one of the most powerful Legendary Pokémon ever! Can Ash and Goh handle a battle against Mewtwo?!