Two daredevil Londoners dubbed 'Night Scape' have made it to the roof of One Canada Square, the second-tallest building in the UK - and they've got it all on tape.
The ten-minute clip uploaded to YouTube shows the teenagers jumping security barriers, setting off alarms and getting their hands on the pyramid at the peak of the 235m building.
While the stunt is impressive, the building owners aren't impressed.
The Canary Wharf Group says they have heightened security since the stunt despite already strict precautions.
But they can't have been that good; doors leading onto the roof on the 50th floor were left unlocked when the teens got to them.
The free-running group have climbed into the Westham football stadium and up skyscrapers, but also have clips of their less successful stunts, including mad dashes from security.
They post their daring manouevres to Youtube and they can all be seen here.