Pokémon : S21 | E44 – Filling the Light with Darkness!

For some reason, Professors Kukui and Burnet are feeling extremely listless, and when Ash gets to school, he discovers that the adults in his friends' lives are in the same boat! The Aether Foundation team has a theory, but they're listless too, so Ash leads the Ultra Guardians (now including Gladion) to investigate. The culprit seems to be something on the other side of an Ultra Wormhole, draining all the energy from the Ultra Auras. Our heroes track down the wormhole and they're excited to see the Legendary Pokémon Lunala emerge—but a mysterious and frightening creature is right on its tail! (Source: Wikipedia)