He was one of a number of writers who submitted scripts to Andrew Cartmel in the waning days of the Sylvester McCoy era of Doctor Who. Had the show not been cancelled, Penswick's unproduced script, Hostage, might have been developed into a televised serial, according to an interview that Penswick gave to the fan magazine, Broadsword.
Penswick later sent in the Hostage script to Peter Darvill-Evans, commissioning editor for the Virgin New Adventures line. This piqued Darvill-Evans' interest, and eventually led to a commissioning of the novel that became The Pit.
Outside of Doctor Who Edit
Prior to the 1988 submission of Hostage, Penswick had at least written a radio play. In the very early 1990s, he attempted to write for Casualty at the time that Andrew Cartmel was its script editor. He was commissioned in 1992, but his script was never produced — probably because Cartmel left before the script could go into production. While he was negotiating this failed Casualty script, he wrote a 90-minute film called Children of the Morning, which Andrew Cartmel had placed before the Radio Times Drama Awards for consideration. Penswick was a recurring contributor to at least two 21st century projects edited by Jean-Marc and Randy Lofficier. In July 2011, his short story, The Two Doctors, appeared in Doctor Omega and the Shadowmen, a short story anthology involving a French analogue to the First Doctor. He also contributed to Volumes 6 and 9 of the Tales of the Shadowmen anthology series.
In June 2012, his short script, Parental Love, was chosen for the 50 Kisses competition, which encouraged young filmmakers to make and upload a project based upon a handful of chosen scripts. The competition, which celebrated the theme of "love", allowed Penswick to write a script which combined his interests in the supernatural and child care.
Outside writing Edit
Penswick was a child protection advisor in addition to being a writer. This work took him to locales outside of Britain. Sometimes wrongly assumed by fandom to have "disappeared" after writing The Pit, Penswick in fact simply had another career as a specialised social worker.