Regular cast:
The Doctor (Peter Davison)
Adric (Matthew Waterhouse) until Earthshock Part Four
Nyssa (Sarah Sutton)
Tegan (Janet Fielding)
Regular crew:
Producer: John Nathan-Turner.
Script Editor: Eric Saward on Castrovalva, Kinda, Black Orchid and Time-Flight, Antony Root on Four to Doomsday, The Visitation and Earthshock. (Although credited as script editor on Earthshock, Antony Root did little or no work on it. This was a ploy to avoid crediting Eric Saward as script editor on his own story.)
Production Associate: Angela Smith.
Title Music: Ron Grainer and the 大象传媒 Radiophonic Workshop, arranged by Peter Howell.
Special Sounds: Dick Mills.
A week after K9 and Company was transmitted, Doctor Who itself was back on air for the start of the fifth Doctor's era - in an unfamiliar weekday evening slot, broadcast at the rate of two episodes per week. This was the first time (bar repeats) that the series had ever been moved from its traditional Saturday evening slot, and the change was accepted only reluctantly by the production team.
Christopher H Bidmead had left the team after the expiry of his year's contract and a young writer named Antony Root, who had previously worked at the 大象传媒's TV Drama Script Unit, was given a short attachment to Doctor Who as a replacement script editor. Root started work on the series in January 1981 and ultimately received a credit on three stories (and also a co-credit on K9 and Company), although he commissioned none of them; his involvement was essentially confined to suggesting and performing rewrites and ensuring that scripts were ready in time for recording. Root later went on to a distinguished career as a TV and film producer.
The new permanent script editor was Eric Saward, who was offered the post on the strength of his season nineteen story The Visitation. He joined the team in mid-April 1981, working alongside Root on K9 and Company and on a number of other stories before assuming full responsibility around mid-way through the season's production.
The other important behind-the-scenes change for this season was the discontinuation of Barry Letts' role as the series' executive producer. This was decided upon in August 1981 as it was felt that John Nathan-Turner was by this point sufficiently well established as producer to render such supervision unnecessary.
The apparent abandonment of Tegan at Heathrow was never intended to mark her last appearance in Doctor Who; the aim was simply to create a cliffhanger ending and thus help to maintain viewers' interest over the (now much longer than in the past) break between seasons - an idea also prompted in part by the use of a similar device in Blake's 7. Tegan would therefore return in the first story of the following year's run, which would again be overseen by producer John Nathan-Turner and script editor Eric Saward.
