"like Orpheus looking over his shoulder"

Orpheus is the classical hero who descended into the Underworld to rescue his beloved Eurydice. Orpheus persuaded the god of the underworld to let him take back his wife, but Hades proclaimed that if he were to look back at her as they journeyed back home, she would be lost. He did and she was; he was then doomed to wander the earth in despair.