It all comes down to this. Paddy McGuinness leads a team of celebrities in a gravity-defying, world-first relay highwire walk 100 feet above the London Stadium.

It all comes down to this. Paddy McGuinness leads a team of celebrities in a gravity-defying, world-first relay highwire walk 100 feet above the London Stadium.

The celebs enter the last stage of highwire training in Austria: tackling a knee-trembling walk between two platforms 650 feet in the air, ahead of their final challenge in London.

The celebs enter the last stage of highwire training in Austria: tackling a knee-trembling walk between two platforms 650 feet in the air, ahead of their final challenge in London.

The celebrities are struggling to hold it together as the mental and physical strain of highwire walking starts to take its toll. Then they're confronted with their toughest physical challenge to date, conquering the 400-foot Schlegeis Dam.

The celebrities are struggling to hold it together as the mental and physical strain of highwire walking starts to take its toll. Then they're confronted with their toughest physical challenge to date, conquering the 400-foot Schlegeis Dam.

Paddy McGuinness and a team of celebs head to the Alps to train for a world-first highwire walk. To kick things off, the celebs are eased into their training, with a backwards jump off of Austria's highest suspension bridge.

Paddy McGuinness and a team of celebs head to the Alps to train for a world-first highwire walk. To kick things off, the celebs are eased into their training, with a backwards jump off of Austria's highest suspension bridge.

Paddy McGuinness, Beverley Callard, David Ginola and more arrive in the Austrian Alps for their first challenge: jumping off Austria's highest suspension bridge. Backwards.

Paddy McGuinness, Beverley Callard, David Ginola and more arrive in the Austrian Alps for their first challenge: jumping off Austria's highest suspension bridge. Backwards.