International Rescue's Lady Penelope Creighton-Ward takes the maiden flight of Skyship One, a new luxury aircraft designed by Brains. But the crew has been killed and replaced by men with a plan to destroy International Rescue.
Unjustly forgotten, this is only a fair film but it has some key moments of tension that are very well done. Compared to the TV series and the first movie, "Thunderbirds Are Go", it's a weak and perhaps too padded adventure but like that earlier film it does work on the small screen.
It's just surprising that it was made at all. "Thunderbirds Are Go" was a flop even though it came out at the height of the TV show's popularity and the makers and backers were so surprised at its failure that they thought it must be a fluke. "Thunderbird 6" was commissioned with a larger budget, but completed when the show's success was tailing off. Perhaps knowing what they'd got on their hands, the studio didn't release the film for several months after completion, probably looking for the best slot.
It didn't work: this "Thunderbirds" movie did as badly as the first. It has similar faults in that it doesn't have the epic feel of a film, it has the extended feel of a special TV episode. But it also add some faults of its own: the movie's plot isn't up to the standard of the series.
Visit our "Thunderbirds site" for more of your favorite puppets.
The "Thunderbirds" series is currently showing on BBC1 on Sunday afternoons.