Made by Southern TV in Southampton - the company had spent a fortune in kitting out a boat as an Outside Broadcast Unit, believed to be the first time it had been done in the U.K. There was an idea in addition to covering Cowes Week, they could press it into service for other programming - and Freewheelers was seen as a great opportunity (which explained the many 'boat chase' scenes in multiple episodes.
The survival rate of this series is very hit-and-miss: the only material existing prior to the sixth season, from which point everything exists in full, is the first season (the eight editions comprising "Menace!" and "Recipe for Danger") plus various film inserts. These were preserved by Mike Womersley, film editor on the series.
Producer/director Chris McMaster joined the crew and actor Michael Brennan in spending 3 hours underwater attempting to get a 2-minute scene right.
The show shared its closing theme, Laurie Johnson's track "Private Eye", with Granada TV's groundbreaking journalism series World in Action (1963), which had used it earlier in the 1960s.
The seventh season, in 1972, was a co-production with Sveriges Radio, as the latter half of the run heavily utilised Swedish locations and cast.