P.R.O.B.E.: The Zero Imperative
Roots: Frankenstein. The X-Files episode 'Squeeze' (a serial killer who takes organs from the bodies of his victims). A For Andromeda (growing an advanced humanoid from cell culture). Liz has a copy of Darwin's The Voyage of the Beagle, tying into the story's evolutionary themes and the three creatures are named after Alfred Russell Wallis.
Continuity: The Beagle Program was set up in the 1970s to conduct research into human evolution. Three human-like creatures were created, the first two of which, named Russell and Wallis, had greater brainpower than humans but which died quickly from unknown causes. The third, designated Alfred, suffered heart failure and deteriorated, but killed a staff member, taking his heart and transplanting it into itself. Following this the creature was ordered to be destroyed, but project leader Julius Quilt secretly kept it alive, taking care of it and educating it, and keeping it with him as his secretary, Emmerson. The creature is able to remove organs from its victims without leaving obvious tissue damage, and leaves behind a gelatinous slime. It absorbs most of Julius's body into itself at the end, resulting in a bloated monstrous appearance.
There is no mention of Burke, who applied for a transfer to P.R.O.B.E. at the end of The Devil of Winterborne, so presumably his transfer was rejected.
Location: London and surrounding area, from July 6th .