The show was made on a tight budget and could not afford sophisticated special effects. To achieve the effect of the guns' muzzle flashes, small specks of black paint were carefully painted onto the 35mm negatives, so that they would appear as white flashes on the prints!
The series has not been repeated in Britain since the 1960s, making it impossible to assess its quality.
After its cancellation Gerry anderson was approached by Lew Grade to make puppet shows for ATV. Had Anderson failed to accept, later series such as Thunderbirds and Captain Scarlet might never have been made.