David Blaine has begun his latest stunt, spinning inside a gyroscopic device above the streets of New York.
Blaine will be exposed to the elements during the stunt
Blaine will dangle near Times Square for almost three days before attempting to escape from some shackles.
"This is more difficult than anything I've ever done," Blaine said before he was loaded into the contraption, which was then hoisted up 50ft (15m).
The three spinning steel rings can flip Blaine in various directions up to eight times per minute.
The shackles will be added to Blaine on Thursday, giving him 16 hours to free himself.
The illusionist said his biggest concerns, besides not eating or drinking, were the freezing weather and dizziness.
After the stunt, Blaine will lead 100 underprivileged children chosen by The Salvation Army charity on a shopping spree.
Blaine spent seven days underwater in New York earlier this year
Blaine said the stunt was important to him since The Salvation Army had provided him with clothing when he was a child.
Blaine's previous stunts have included balancing on top of a 100 ft (30 metre) pole, spending 61 hours inside a block of ice and fasting for 44 days in a box over London's River Thames.
Earlier this year, he spent a week in a water-filled globe in New York. He failed to break the world record for holding his breath at the end of the challenge.