The Doctor and Mel visit Paradise Towers, a residential complex that promises a peaceful life to its residents. However, the establishment is far from what its name suggests: A conflict persists among the Kangs, humanesque multicolour beings who gather in opposing gangs based on which colour of the rainbow they bear; killer cleaning robots prowl the halls, and a secret in the complex's basement poses the greatest threat of all.

The Doctor and Ace head for the Psychic Circus on the planet Segonax, where they meet a disparate group of performers and visitors, including a self-centred explorer named Captain Cook, his companion Mags and a biker known as Nord.

A tale of cat lovers, the social circle they inhabit and the power struggles between them.