Robbie Williams, Phil Collins, Cameron Diaz, Justin Bieber, Oscar-winning actor Christoph Waltz, supermodel Sara Nuru and Cher were among the guests taking part when student Samuel Koch's attempted stunt involving a moving car went tragically wrong on Germany's Wetten Dass! - Want to Bet? - programme.
He bet host Thomas Gottschalk that, using springs on his feet called power jumpers or kangaroo shoes, he could leap over five cars driving towards him at 15.5mph.
After his fourth attempt, where he tried jump over an Audi driven by his father Christoph, he landed on his face.
Realising the 23-year-old-contestant wasn't moving, Gottschalk and his assistant Michelle Hunziker rushed towards the young man, screaming for a doctor.
A terrible hush fell over the audience and the ZDF network bosses immediately pulled the plug on the show - centred around celebrities performing and making bets with contestants about whether or not they can pull off a stunt - being broadcast. It was replaced with music and clips from previous shows.
Canadian teen idol Bieber was due to make an appearance shortly after Koch's appearance and later asked his followers on the Twitter website to pray for the injured German.
Meanwhile, Williams and his Take That bandmates left the hall, with Williams heard to say into his mobile phone: "Call me immediately when you know how he's doing."
This was the first time in the more than 26-year history of the show that such a serious accident has occured.
Millions of the viewing public in Germany, Austria and Switzerland tune in to make it the most watched programme on the continent.
After around 30 minutes showing only the old recordings following the accident, bosses on the ZDF network switched back live to Duesseldorf, where Gottschalk said that Koch "can feel his legs and that he also can speak".
"However, nobody can pretend to be jolly after witnessing the accident," Gottschalk said.
"This is the first time in my career the absolutely worst thing has happened. I'm utterly sorry," Gottschalk added.
He asked the audience to understand how hard it was for him to stop the show for the first time in his career.
Later in the evening, the ZDF evening news linked directly to Gottschalk to ask about Koch's condition, but he had no news except to say his parents were at his bedside.
At shortly after 12:35am a doctor from the University Clinic in Dusseldorf announced that the young man was undergoing emergency surgery.
His condition was described as stable last night.