The colour master videotape was wiped by the BBC in the 1970s and although colour versions were sold overseas, only 16mm black-and-white film prints were retained by BBC enterprises. However, this episode was restored to colour for the DVD release in 2013 using the chroma dots discovered in the film prints.
John Levene injured his leg after falling badly while being hauled out of the truck's cab by a stuntman playing one of the criminals.
In the original script, the Brigadier was captured at Stangmoor Prison along with the Doctor and Jo. Under the influence of the Master's hypnotism, he had the missile's route changed to enable the Master's men to hijack it.
This episode was watched by 7.4 million viewers on its original transmission.