The roar of an engine heralds the launch of Thunderbird 3, emerging from beneath the ground and travelling through a retro-future roundhouse as it launches for another daring rescue. Now, with behind the scenes gems from the archive, Thunderbirds Unseen uncovers the making of this iconic sequence. In this instalment of Thunderbirds Unseen EXTRA – our behind the scenes investigation of the creation of Gerry and Sylvia Anderson's classic television series – we take an in-depth... some would say too in-depth... look at the Thunderbird 3 launch sequence. With the help of newly unearthed 35mm film and studio documentation, Thunderbirds Unseen series challenges some of the "established" facts of the series' early days and uncover footage unseen for sixty years. https://www.youtube.com/watch?v=oNiBH3PUl60