Callanna

Callanna was a sentient planet which responded to the wants and needs of those upon it. (AUDIO: Madquake) The Fifth Doctor left Nyssa, Tegan Jovanka and Marc there after Marc's partial cyber-conversion (AUDIO: Conversion) and, during their stay, they worked with Steppa Westma Cotter-Thatch Slitheen to stop Bella and Grumma from using an atmosphere scoop to steal the planet's atmosphere. (AUDIO: Madquake)