Disclaimer: this is a work of fiction.
Part Eleven: Seasons 26 to 27 (1989-90)
Andrew Cartmel left the role of Script Editor after only two-and-a-half years, midway through production of Doctor Who’s 27th season, having been transferred to another BBC show. By this time his ‘Masterplan’ was a well-established part of the programme, subtly introducing a darker feel to some, though by no means all, of the serials in each season.
Colin Baker was keen that Cartmel’s successor should keep this aspect of the series, which he enjoyed immensely (even though it had worked the opposite way to his original intention; light-to-dark instead of dark-to-light). JNT had private reservations about how long they could sustain the subtle hinting at the Doctor’s past without exhausting the patience of the viewers. Audience figures remained high throughout this period, however, so the seemingly winning-formula was not tampered with.
The most memorable serial from these two seasons is probably Ice Time, which saw Sophie Aldred’s Ace depart in a story featuring the Ice Warriors and the Time Lords. However, this was to be a temporary departure - reminiscent of Tegan’s between seasons 19 and 20 - and Ace was to return in season 28.