In The Face Behind the Lead Mask!, Superboy encounters a mysterious figure wearing a lead-lined mask who seems to know his every move. When the stranger’s identity is finally revealed, it shocks both Clark Kent and readers alike: the man beneath the mask is Superboy’s future self — Superman! Having traveled back through time to correct a cosmic disturbance, the adult Superman must conceal his face to prevent a temporal paradox. The story explores the paradoxes of fate and identity, underscoring the emotional tension of a hero forced to hide from his younger self.