Flight instructor Jamie Forbes radios to help land a plane for a woman whose pilot husband passed out right at the controls. For Jamie, there is nothing heroic about this: that’s why instructors exist, to help novice pilots. But soon Maria tells reporters that a stranger appeared on her plane from somewhere, who hypnotized her and led her until the landing. And then Jamie meets his own stranger-mentor and begins to understand the Main Secret: each of us, step by step, creates what seems to us a “dense” world around us. The most interesting secrets are those to which the key is right under our noses. The most amazing moments in life are when we suddenly realize something we always knew...