Nevertheless, two films were made — with puppets. Thunderbirds Are Go cost £250,000 and flopped in 1966. Thunderbird 6 cost £300,000 and flopped in 1968. The omens don't seem good.

Except that, this time, it's real people. But lose the strings, the fixed expressions and the shiny skin — in short, the puppets — and what do you have?

A somewhat daft story about International Rescue, a charitable but secret organisation set up by a wealthy widower, Jeff Tracy. His sons keep flying around rescuing people in odd vehicles and there's a blonde It girl named Lady Penelope with a pink Rolls-Royce and a chauffeur called Parker. Somehow it made sense when they were puppets, but real people?