The 6th Series was originally broadcast between the 15th May and 26th June 1978, consisting of 6 episodes, three two part stories.

1978 saw changes being made, starting with Elizabeth's absence through most of Series 6 due to Elizabeth Adare's pregnancy (on screen Elizabeth is working on diplomatic missions for the Galactic Federation and appears only briefly on a screen so as to hide the actress's condition). In her place came Hsui Tai, played by Japanese actress Misako Koba, whose poor grasp of English made her hard to understand, and Nicholas Young later recalled that he and other actors found this difficult during production. Koba had no previous acting experience and had been suggested for the role by her actor husband. 

A new Lab set was introduced with a smaller but now mobile TIM and the jaunting belts were replaced by the rather cheap looking jaunting bands (worn on the wrists). These changes were forced on the production team following a fire at the Thames storerooms. The new Lab acted as both base and home for the Tomorrow People as they were now seen to be sleeping in their own cabins there. It was noticeably smaller than the previous set, which freed up more space in the studio for the designers to utilise on other sets.

 The 6 episodes were produced sporadically through 1977 (a combination of Price writing scripts as and when it fitted with his other production commitments and a number of strikes at ITV over the year) and finally launched in the Spring of 78. Such was Holoway's popularity that he was featured on the cover of TV Times to promote the start of the season.