David Agnew was a pseudonym employed by Graham Williams and others. The BBC in the late 1970's took a dim view as to Producers and Script Editors commissioning themselves, so when the occasion did arise, then-Doctor Who Producer Williams disguised his actual authorship. 2 entertain did a feature on The Invasion of Time DVD called The Elusive David Agnew, It was entiled this as David Agnew never turned up to meetings and when phoned a message had to be left.
- Anthony Read, (the Script Editor, at that time) collaborated with Graham Williams on the scripts for The Invasion of Time, written at the last minute to replace a script by David Weir which would have proved too expensive to film.
- Douglas Adams (the then-current Script Editor) and Graham Williams on City of Death as a late replacement for David Fisher's A Gamble With Time.
- The same team of Douglas Adams and Graham Williams on Shada.
As a joke, the short story Special Occasions: 4. Playing with Toys in Short Trips and Side Steps also had the pseudonym David Agnew.