Super-Hero partners Scott Lang and Hope van Dyne, along with with Hope's parents Janet van Dyne and Hank Pym, and Scott's daughter Cassie Lang, find themselves exploring the Quantum Realm, interacting with strange new creatures and embarking on an adventure that will push them beyond the limits of what they thought possible.

On his ninth birthday, young Gwyn (Osian Roberts), who lives on a remote hill farm in Wales, receives five strange gifts from his grandmother (Siân Phillips): a piece of seaweed, a yellow scarf, a tin whistle, a metal brooch and a small broken horse. Gwyn offers the brooch to the wind and receives back a tiny silvery spider - Arianwen, the snow spider - confirming that, as his grandmother had already guessed, he has inherited magical powers from his Celtic ancestor Gwydyon, a powerful magician whose exploits are described in the fourth book ("Math Son of Mathonwy") of the Mabinogion. With the help of the snow spider, Gwyn embarks on adventures involving other worlds of snow and silver, as he attempts to solve the five-year-old mystery of his sister Beth's disappearance in a snow storm.

Young magician Gywn and his friend Nia have been warned to stay away from Emlyn Llewelyn, the strange boy who claims his mother lives on the moon. And yet, a mysterious magic continues to draw them to him. But why? It's up to Gwyn and Nia to solve the mystery, with the help of Arianwen, the Snow Spider.

Gwyn can feel danger coming in the wind. Somehow he knows the warnings have to do with the broken toy horse that holds the evil spirit of a prince who lived long ago. When Gwyn discovers that the prince's dark soul has escaped from the horse and is seeking revenge Gwyn, Emlyn, and Nia have to figure out how to save the mysterious soldier who claims to be Nia's distant cousin. With the help of the Snow Spider, can they recapture the prince's soul without hurting the Chestnut soldier?

Black Manta seeks revenge on Aquaman for his father's death. Wielding the Black Trident's power, he becomes a formidable foe. To defend Atlantis, Arthur (Aquaman) forges an alliance with his imprisoned brother. They must protect the kingdom.