With her red London bus on course for the future, Iris runs slap-bang into the past! Materialising aboard Radio Yesterday, a space station broadcasting golden oldies to Earth's colonies, Panda finds something sinister in the air-conditioning and Iris comes face to face with her long-lost husband...(no, really!) As Iris, Panda and the crew of Radio Yesterday experience the true power of music, the evil Naxian hordes are poised to transmit a groovy message of death...to the entire galaxy!