It was a blast from the past for 'Thunderbirds' fans as the iconic yellow submarine known as Thunderbird 4 was seen taking a spin on the River Thames in London today (April 2nd 2015) ahead of the new ITV series, 'Thunderbirds Are Go'.

Thunderbirds Are Go Thames stunt
Thunderbird 4 hit the River Thames today

As part of the launch of the new series, which makes its return 50 years after it first aired in the UK, the stunt took place next to baffled onlookers; with the yellow rescuer cruising along aimlessly against a backdrop of the Houses of Parliament, Big Ben and the Tower Bridge. It looked virtually indistinguishable from the vehicle that first gripped imaginations everywhere in 1965, apart from being slightly larger at fifteen feet. It took a considerable 6 weeks to build this fibreglass fantasy and all in the name of traditional puppetry TV.

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''Thunderbirds' is a classic British show, so we wanted to celebrate the launch of the new series Thunderbirds Are Go on ITV by building one of the iconic vehicles and surprising commuters on their way to work', said ITV's director of marketing Adrian Last. 'Seeing Thunderbird 4 cruising down the River Thames brings back a feeling of nostalgia for those that remember the show from 50 years ago and puts a smile on the face of the young.'

Thunderbirds Are Go Thames stunt 2
Series to return this weekend

'Thunderbirds' was created by Gerry Anderson and Sylvia Anderson; pioneers of children's television and, indeed, marionette puppetry, creating a unique style known as Supermarionation. The series follows the adventures of Jeff Tracy and his family, who travel through space, air, water and land to rescue people from compromising situations. The upcoming new series will be animation and live-action, featuring the voices of Rosamund Pike, Thomas Brodie-Sangster and Rasmus Hardiker among others, and will welcome back original cast member David Graham as Aloysius Parker.

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'Thunderbirds Are Go' will air as a double episode special on April 4th 2015 at 5pm, with subsequent episodes being aired at 8am.