Robert Newman was the sexton of Christ Church (known today as the Old North Church), and a personal friend of Paul Revere's. It was Newman who hung the lanterns from church steeple to warn riders in Charlestown that the British were marching on Lexington and Concord. Two lanterns - indicating that the British were travelling by sea.
(And because it's a pet peeve of mine - you may have heard that Newman put up the lanterns to warn Revere about the British approach - it's one of those historical details everyone seems to get wrong. Revere already knew about the raid, and in fact had been the one to pass the knowledge on the Newman. The lanterns were meant as a warning to lookouts in Charlestown - a backup in case Revere was caught before he managed to leave town. Please learn this so you can impress girls on first dates, as I do, though they often seem so overwhelmed by it they rarely call again. That's the power of knowledge, and it's dangerous).
Newman had some difficulty with his clandestine plan, though. His family home was serving as a boarding house, and several British officers were staying there. Newman managed to elude them by saying he was tired, going to bed, and escaping out a side window, like something out of a cartoon. His friend, John Pulling, helped him get the lantern to the top of the tower while a third man guarded the church door.
Newman was later questioned about his actions that night - possibly because a twenty-something announcing he's going to bed early is inherently suspicious - but he talked his way out of arrest, and fled Boston.
When Newman returned to the city, he went back to his old job as church sexton. There's evidence he took money to show tourists around the church crypt - including displaying the body of John Pitcairn. Which might have something to do with Newman being replaced by a new sexton in 1788.