INTRODUCING THE UNIT 'FAMILY'!

After the success of his premiere full-colour season, Jon Pertwee cemented his era as the Third Doctor with his successive year, becoming a delighted 'mother hen' of sorts both on screen and off, with the colourful and action-packed birth of the new UNIT 'family' era designed by producer Barry Letts and script editor Terrance Dicks to win over new audiences, introducing appealing new characters to the show on the side of good (notably Katy Manning as lovably dizzy Jo Grant and Richard Franklin as Captain Mike Yates), and for evil (the sinister new The Master, as played triumphantly by Roger Delgado). Showcasing the new feel for the series was a great publicity shoot specially taken by the Radio Times magazine to promote the 1971 series, of which filming of Terror of the Autons, controversially opening season eight, would begin filming this month back in September, 1970.

Doctor Who's Katy Manning remembers "closest friend" Jon Pertwee | Radio Times

Part of the new line-up for the series. 

Note The Master's Horsebox TARDIS and the not fully constructed TARDIS police box prop with its bottom flooring step missing.

The scene-stealing The Master is the cover star of the Radio Times, much to the then chagrin of Pertwee.