I have a less ominous version of this tale. When studying for quals I put all of the theorems in analysis I might need to prove in a little hand-written booklet (about 5x8cm) so I could quiz myself on the subway. These theorems became my whole world. I was staring at a proof when a man, puzzled by my state of concentration, asked “are those… your prayers?”
I was disoriented by the interruption. But on a moment’s swift reflection I could only answer: “Yes.”