Therefore, its known narrative elements are not a part of the Doctor Who universe as we, on this Wiki, choose to define it. It may have been the basis for a similar story in another medium, however — and that story may indeed be valid.
The Talons of Weng-Chiang was a story concept in John Leekley's series bible for Amblin Entertainment's proposed 1990s Doctor Who television show. It was based on the Fourth Doctor story The Talons of Weng-Chiang.
The Chinese Tong of the Black Scorpion, led by Weng-Chiang, has been committing a series of murders in New York City. The Doctor identifies Weng-Chiang as far-future war criminal Magnus Greel, who needs to absorb others' energy to survive, and he helps a NYPD cop find Greel' lair and bring him to justice.