Written by Philip Martin, this story was submitted on 28 December 1983 and dealt with an alien race returning to Earth to discover their "humanity" experiment has failed. The story involved the TARDIS alerting the Doctor to the fact that a regeneration is in progress nearby, suggesting the presence of a fellow Timelord. The Doctor instead find the elite of the Doomwraiths emerging, reconstituted, as shimmering metal columns with many moving strips and a deadly purpose. The Wraiths find that human evolution has failed, and mankind has not taken on their form; they will thus release a plague to destroy humanity, relocate the missing section of genetic code and repopulate Earth themselves. The Doctor and Peri discover that the Doomwraiths themselves have a genetic flaw which gives them the impulse to destroy. The Doctor manages to destroy the discovered code block, but says that the Doomwraiths may have left their legacy on other worlds. On 9 March 1984, Saward noted that the story idea would need further development before he could assess it for commissioning.