The best example of this is Tommy Cooper, a British magician / comedian known for his slapstick style. He'd often stumble steps in his act, or mess up on purpos

The best example of this is Tommy Cooper, a British magician / comedian known for his slapstick style. He'd often stumble steps in his act, or mess up on purpose so you could never really tell what was planned or not. When he had a heart attack on stage, people thought it was part of his act and the curtain closed to a standing ovation. https://www.youtube.com/watch?v=r8zi7vcnjVc https://www.youtube.com/watch?v=r8zi7vcnjVc