At 3am this morning, nutcase Aussie FMX rider Robbie Maddison jumped his bike over Tower Bridge - from one raised section to the other, soaring over the Thames while performing a casual backflip.
It was the latest of his daredevil-esque stunts, which have seen him jump over an entire football pitch and leap onto the Arc de Triomphe replica in Vegas. This time things were kept below the media radar to keep the cheery Health and Safety officers happy, although Top Gear was given a cheeky tip-off.
So when the bridge’s huge cantilevers swung open this morning, we were on the riverbank to watch Robbie do his thing. There was a guerrilla feel to the action; a sort of swoop-in, swoop-out operation. As soon as the road was closed, Robbie's team bolted his ramps into place, before Maddo then fired up his Yamaha - its two-stroke engine echoing off the bridge like an angry chainsaw.
It was Robbie's first time on the bridge - this isn't the sort of thing you can practice without landing on the top deck of the 263 to Fulham. So he took a quick sighting run up the ramp before doing it for real, ignoring the spotlights and flashbulbs while trying not to ditch in the river 100 feet below (he was wearing a lifejacket just in case...).
A quick no-handed backflip later and - judging by the whoops and cheers of his entourage - he was safely plonked on the other side. He made it look simple, as easy as skipping over a small puddle. It's the sort of trick that made Evel Knievel famous, and Robbie shares a similar sort of showmanship. He's also a nutter.
The jump was a curtain-raiser to the Red Bull X-Fighters show in Battersea on August 22. Robbie will be there, along with a load of other gnarly men with tattoos, pulling tricks around the power station before crashing in messy heaps with their teeth smashed out. These guys are tough, but when they get it right, nothing is more spectacular.
Despite the hush-hush build-up for the Tower Bridge stunt, Top Gear flew out to California to hang out with Robbie as he prepared for the jump. You can find out how it did it, and what makes him tick, in the September issue of Top Gear magazine, out on August 12.
In the meantime, check out our gallery and a video of the jump: