P.R.O.B.E. - The Zero Imperative (1994)
This was the first in a series of Doctor Who spin-offs written by Mark Gatiss and produced by BBV Productions.
Now working for P.R.O.B.E. (The Preternatural Research Bureau) - an organisation tasked with investigating paranormal activities - former UNIT scientific advisor Doctor Liz Shaw and her assistant Bayliss are investigating a series of bizarre murders, which have taken place near a soon-to-be-closed psychiatric hospital.
When the hospital is unexpectedly reprieved by rich Industrialist Peter Russell events takes a shocking twist.
Are the incumbent director of the clinic, Doctor Dove and his predecessor Doctor O'Kane harbouring the killer?
What age-old horror is hidden in the hospital grounds, and what exactly is the secret of room zero?