Lalla Ward was unhappy with Romana's leaving scene, as she felt it was rushed and dispassionate. John Nathan-Turner was adamant that he did not want elements of soap opera to creep into Doctor Who (1963).
When the Doctor said "If I'm not back for whatever reason in 13 and a half minutes I want you to de-materialize", there were 13 and a half minutes left in the episode.
This episode was watched by 7.8 million viewers on its original transmission.
This episode marked the last appearance of Romana (played by Lalla Ward), as well as K9. However, K9 would reappear in the spin-off K-9 and Company: A Girl's Best Friend (1981) and also in the 20th Anniversary special The Five Doctors (1983) (as would Ward, by use of previously unused footage filmed in 1979). K9 would reappear again in the new Doctor Who series in the episode "School Reunion" in 2006.