Ky transports himself and Jo down to Solos and the Marshal only agrees to help her if the Doctor assists Professor Jaeger in altering Solos' atmosphere.

Starring:

Elisabeth Sladen, Frazer Hines, Jacqueline Hill, John Levene, John Scott Martin, Jon Pertwee, Katy Manning, Nicholas Courtney, Pat Gorman, Patrick Troughton, Peter Davison, Tom Baker, William Hartnell, William Russell

Genre:

Adventure, Drama, Sci-Fi