Wales, 1959. A top-secret US satellite has mysteriously gone missing. This could have something to do with the arrival of a party of alien tourists en route to Disneyland, amongst their number Mel and the Doctor, and the Queen of the Chimerons - who's fleeing the Bannermen and their genocidal leader Gavrok...

Mel's just discovered something very interesting about the life cycle of her new friend and the Doctor has been cornered by an alien bounty hunter wearing blue suede shoes.

As Billy and Ray do what they can to help save Delta and the baby, the Doctor and Goronwy the beekeeper face Gavrok and his Bannermen one last time...