The following story contains images some readers may find disturbing.

The following contains spoilers in Superman: Space Age #1, on sale now from DC Comics.

DC's Superman: Space Age #1 reveals a dark secret about Jonathan Kent from during his time in World War II.

Superman: Space Age #1 comes from writer Mark Russell, artist Michael "Spike" Allred, colorist Laura Allred and letterer Dave Sharpe. In the issue, Jonathan and Clark Kent are sharing beers when Jonathan tells Superman a story from when he served during World War II. In 1944, Jonathan was sent to the island of Saipan and told to clear out the surrounding caves. "We figured we'd round up all the prisoners in an afternoon," Jonathan recalls. "One of the prisoners detonated himself, taking the other prisoners and half our unit with him. I never knew men were capable of such things. As beaten as they were, they had no thought of surrendering. I knew at that moment we'd have to kill every soldier on that island."

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Jonathan continues to explain there was never any telling as to who -- soldiers or civilians -- was hiding in the caves. "One trick we learned was to look for burning cigarettes. Only the soldiers had cigarettes, which they'd be savin' for months. Sometimes just for the occasion. The occasion of their death. It was a small detail, but big enough that it saved my life a couple of times."

One time, Jonathan saw a flame and, assuming it was a soldier, fired his weapon. "He must've used the lighter to find his way out of the cave," he continues. "He couldn't have been more than twelve. And I'd shot him. They say that you see the face of everyone you've ever killed when you close your eyes to go to sleep. But the truth is worse. After a while, you don't see them at all. The dead disappear because we need them to."

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Jonathan says he returned to Smallville with the feeling that everything was now "broken." Looking for a sign from the universe, Clark crashed down to Earth a short while later -- an event Jonathan describes as "miraculous." Superman: Space Age goes on to tell the story of Clark's earliest days as Superman, with the three-part series then leading up to the events of Crisis on Infinite Earths​​​​​​.

Superman: Space Age #1 features cover art by Michael and Laura Allred and variant cover art by Steve Rude and Nick Derington. The issue is on sale now from DC.

Source: DC Comics