Due to the chaotic filming schedule implemented on Thunderbirds, necessitated by the expansion of each episode from 25 to 50 minutes, working out any meaningful production order is, it seems, impossible. As can be seen in some of the contemporary behind the scenes films, sections of several episodes would be in production simultaneously. For instance, in one black and white film, we see (or hear) parts of City of Fire, Security Hazard and The Cham-Cham in production on the puppet stages, whilst on the effects stages we see The Man From MI.5 and Cry Wolf being shot.

 

This illustrates a couple of points about the production of Thunderbirds. Firstly, it shows that the special effects unit was operating several weeks behind the puppet stages, as The Man From MI.5 and Cry Wolf were filmed by the puppet unit before Security Hazard and The Cham-Cham. Secondly, City of Fire was an early episode in production (the original half hour script survives and we know that it was Director David Elliott’s first film for the series) so the sections being shot on the puppet stage must be ‘filler’ material to extend the episode. So is it an early episode in the production order because it was one of the first in production, or is it a late episode because significant chunks were filmed towards the end of the first series? Unfortunately, what paperwork does survive only serves to confuse matters, indicating that Alan Pattillo originally directed Sun Probe and The Mighty Atom, instead of David Lane (as credited), and doesn’t give a clear view of what happened where. Unfortunately, it seems that it will never be possible to deduce the true production order.

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Episodes are listed in the ITC Recommended Broadcast Order. Episodes marked with an asterix are believed (by the author) to have been shot as half-hour episodes. Transmission dates are for ATV Midlands.