These films, at £85,000 each to make, were considered very expensive at the time, but this was rewarded when most of the films were sold to other countries, with 'The Prison; and 'Regan' going to 47 countries alone.

'Regan' was particularly seen as having potential for a series, especially after receiving high TV ratings. Immediately work began on 13 one-hour episodes. Most elements of the original film remained, apart from the title that got lost somehow - and 'Regan' soon became 'The Sweeney' with one series and 20 episodes.