The "Z Cars" theme (traditional folk tune "Johnny Todd") proved to be so popular that Liverpool-based soccer side, Everton F.C., immortalized it as their theme tune as the teams enter onto the field, a tradition that remains. Elton John enjoyed the theme so much that he also adopted it at the club at which he presided as chairman, Watford.
Whilst taping 'moving vehicle' shots in studio, as technology was nowhere near as advanced as it is currently, it was so much simpler to use a 'stripped' version of the vehicles involved. Many such were missing their entire front ends and windscreens to facilitate both filming and sound recording. Continuous film was played on the screen behind, to give the impression that the vehicle was actually on the move during recording. Immediately after one such shot, actor Brian Blessed (PC 'Fancy' Smith) stepped out of the Z-car, and, having left his cap on the dashboard, reached in through the vacant windscreen space to retrieve it. Blessed himself spoke of this during a talk show some years later, but apparently neither the film crew nor the director noticed.
Also available in a computer colorized version.