Written by Peter Ling & Hazel Adair, this story developed out of plans by producer Nathan-Turner to create a sequel to the 1960s soap opera "Compact", entitled "Impact". When, after drafting three or four scripts for the proposed "Impact", Nathan-Turner informed the pair that plans for the soap had been cancelled, the producer offered them the opportunity to write for "Doctor Who" as a form of compensation. A scene breakdown (whittled down from six parts to four) was commissioned on 12 July 1983, but after three months of development on the scripts, during which the story was restructured into two 45-minute episodes, it was ultimately rejected. The plot involves the disappearance of various people on Earth, which leads the Doctor and Peri to the planet Hexagora where the Doctor becomes romantically involved with Queen Zafia who is trying to save the insect race of Hexagora from destruction through a plan to infiltrate and take over Earth. It was later adapted as "Hexagora" by Paul Finch for Big Finish's "The Lost Stories" with Tegan and Nyssa in November 2011.