Welles Crowther was a young equities trader and former Boston College lacrosse player. On September 11, 2001, survivors in the South Tower’s burning 78th floor sky lobby saw a young man appear with a red bandanna over his face. One survivor remembered him saying, “I found the stairs, follow me. Only help the ones that you can help.” They got up and followed. He made at least two trips to that floor and guided as many as 12 people to safety. Welles could have saved himself, but he died when the tower collapsed. Only later did survivors identify him as the mysterious man in the red bandanna. Heroes don’t always get to see the difference they make.