This is James Heptonstall. He wanted to see if he could run faster than the tube. So he decided to race it from Mansion House to Cannon Street.
Ready, steady, go!
To beat the tube, he had 80 seconds to run through the station at Mansion House...
...through (or possibly over) the ticket barriers...
...through the streets of London...
...to Cannon Street station...
...through (over?) the Cannon Street barriers...
...and back on to the same carriage he had been riding 80 seconds before.
Amazing.
London's commuters are very impressed.
80 seconds to race the Tube @NoelsieC @JHepto!?!! It takes me that long to fish my Oyster card from the bottom of my handbag! #racethetube
Have a crack at this next time you leave your brolly on the train http://t.co/RLJU4UGG0S #racethetube
Would love to see him do this during rush hour. #Racethetube https://t.co/qvbt3GE9Hi
Especially this lady.
Watch the incredible video here.
View this video on YouTube
Or if you prefer long distance running, watch the pair's other video, which shows Carroll racing the tube all the way from Moorgate to St James's Park.
View this video on YouTube
That's 11 stations on the Circle Line, which takes the train 19 minutes, or a 5k run, including 2 ticket barriers, 70 steps, and a fence.
Mr Heptonstall told the Evening Standard that they may try another tube race in the future.
So if you see some guy running at breakneck pace through the tunnels of Kings Cross with a GoPro round his head, don't panic.