Callan (TV series) is run by Colonel Hunter. ("Hunter" is a pseudonym for the current Section Chief, like the C of SIS.) The Section removes those who pose a danger to the "innocent" by persuasion, blackmail, extortion or death. David Callan had been the Section's top operator but he had become too curious about his targets and the rationale for their removal. The Section considered him vulnerable, volatile and dangerous and had laid him off to a dead-end book-keeping job for an ungrateful employer. ABC then commissioned a series of six episodes in 1967. In the first episode Callan rejoins the section in
Callan (TV series) featuring all 13 episodes from series 4. It has not yet been decided whether further series will be released to DVD in Region 1. Clear Vision Video released three DVDs subtitled "Series 1 Parts 1 – 3 of 3", also available in a box titled "Callan – The Complete Series One", in 2001. In fact these DVDs comprise the nine episodes of Series 3, the first colour series, although the back cover blurbs incorrectly state that "This edition comes from the first series that was ever shown on Thames Television in 1970". Prism Leisure released the cinema film as "Callan