This was the first written script for the show by Tony Barwick. He would also write the scripts for 17 more episodes of the series, as he was Script Editor right from the start of the series. Barwick was not new to this type or script-writing as he assisted Thunderbirds Script Editor Alan Pattillo in doubling the length of existing 30-minute scripts. Barwick also wrote the teleplay's for two second season Thunderbirds episodes, Lord Parker's 'Oliday (1966) and Ricochet (1966).
The VIP oil tanker previous appeared slightly modified and in a different color in the Thunderbirds episode Path of Destruction (1966).
The ambulance seen at the very end of the episode previously appeared in Thunderbirds as the yellow Crablogger command center in Path of Destruction (1966).
This is the first of three episodes in which dialogue indicates that it takes place on 10 July (the birthday of series writer/script editor Tony Barwick), the others being Treble Cross (1968) and the closing scene of Flight to Atlantica (1968). As a result, fans of the series observe 10 July as "International Captain Scarlet Day".
When the series began a re-run on BBC Two in September 2001, this episode was originally due to be broadcast on 17 September as the second episode, matching the order of production. However, it was postponed due to similarities between the story (featuring a plane hi-jacked by the Mysterons) and the terrorist attacks of earlier that month. Around this time, the Captain Scarlet pages on the website of the series' distributor, Carlton, were briefly taken offline. The episode was ultimately broadcast on 10 December 2001.