Seven decades of American comedy were fundamentally altered by a broken sewing machine and a severe case of pneumonia. It sounds like an elaborate joke, but it's historical fact, the unlikely chain of dominoes that gave us one of entertainment's most important figures.

This deep dive explores Carl Reiner, the architect of the modern sitcom, Mel Brooks's comedic soulmate, and Steve Martin's mentor. His career is a master class in how facilitating others, stepping out of the spotlight and checking your ego, can ultimately cement your own legacy.

• How a WPA drama workshop pulled a teenage machinist from the Bronx into the arts
• The pneumonia and Hamlet audition that kept him out of combat in WWII
• The 2000 Year Old Man bit that started as a party trick at Norman Lear's house
• Why he stepped aside from his own pil ...