After a stroke had rendered him blind 10 years ago, Olmedini started working the trains with an assistant. To other Ecuadoreans who encounter him, he is a welcome link to their childhood, when the magician appeared on television shows and judged beauty pageants. “He was a fabulous magician back home,” Mr. Permuth said. “He opened for Menudo once. He was a celebrity.”

He still is, just on a smaller, moving stage.