Callan began writing for radio at the outset of his career. He adapted
The Dead Secret by
Wilkie Collins and
Scales of Justice by Dame
Ngaio Marsh for RTÉ Radio, and wrote the original plays
The Train and
Tripp. He contributed more than 20 plays to the Dan Treston-produced series Treasure House, dramatising the lives of scientists and artists from
Johannes Kepler to
Edgar Allan Poe and
H. G. Wells. Callan's first screenplay was the crime series
The Burke Enigma, a six-hour film production for
RTÉ, which starred
Ray McAnally and
Donal McCann, and went forward as RTÉ's drama entry for the 1979
Prix Italia. According to Callan, this work was "influenced by the
film noir I loved as a kid, and by
Robert Altman's (filming) style." Subsequently, Callan joined
BBC television drama in London, where he story-edited the detective series
Shoestring. Simultaneously, at
ITV, he wrote for the action series
The Professionals. In the 1980s, Callan collaborated with
Frederick Forsyth on
Public Broadcasting Service-aired adaptations of Forsyth's stories
Privilege and
A Careful Man (Mobil Showcase). Collaborating with
Anthony Shaffer, Callan was commissioned in 1987 by
HBO to write
The Negotiator, based on a treatment by Forsyth. The series was announced but never filmed and Forsyth later redeveloped the outline into a novel. He was commissioned to write a two part episode for the BBC of
Doctor Who (entitled "
The Children of January"). This was in final revision when the series was suspended under Jonathan Nathan-Turner's tenure as producer in 1985. On his website, Callan responded to an enquiry on this subject thus:I wrote a two-parter called
The Children of January. It was to be a season closer, not a series termination. But the BBC decided in mid-season that the show had run its course and, in the middle eighties, I think they were right. But I loved my episode, which was delivered late in 1985. I created a race of runaway proto-humans called the Z'ros, sort of 'human bees', of which I still have the fondest nightmares.
The Children of January, incidentally, refers to renegade outcasts of a dawning "parallel universe" civilisation that was abandoned. In 2011, Callan wrote and produced Channel 4's
Sounds from the Cities. The series was presented by actor Mathew Horne, and featured live performances from Imelda May, K.T. Tunstall, Jon Fratelli, Joy Formidable and Gruff Rhys of Super Furry Animals. ==
Doctor Who: The Children of January==