WARNING: The following article contains spoilers for Superman: Up in the Sky #1-4 by Tom King, Andy Kubert and Sandra Hope, on sale now.

Superman: Up in the Sky is a space odyssey that has Superman traveling to the end of the universe in search of a little girl, who was taken "up, up in the sky" by aliens after a brutal Gotham home invasion. Since the moment Batman enlisted Superman's help in Issue 1, the Kryptonian has been wrestling not only with the challenge of locating the missing child but also with his own psyche.

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Issue #1 saw Clark Kent having to weigh up his monumental responsibilities on Earth against heading off into space to save little Alice. After much internal strife, he chooses the latter and sets off to do the impossible: find a vulnerable human girl who could be anywhere in the vast, never-ending universe. An unexpected but well-formed blend of completely far out Silver Age-style storytelling and 21st-century psychoanalysis ensues.

With the reluctant help of the Rannians, Superman is attached to an elaborate machine that allows him to absorb and trace residual zeta beams -- the only hope he has of tracking the aliens who took the girl. There is only one line of code that remains of the zeta beams through which to follow the trail. That code is, "I can't," and those words become a recurring theme throughout the story. The Rannians warn that the beams will inevitably drive Superman mad and kill him. They keep telling him he "can't" and he persists nonetheless.

What follows takes place as much in Superman's mind as it does in the vastness of space.

He comes to terms with guilt and confusion, steps into a boxing ring with an intergalactic champ, fights alongside Sgt. Rock and Easy Company (a great tribute to Joe Kubert from his son Andy), and has his life saved at the tragic expense of another. He even deals with the worst possible challenge of all while trying to make an intergalactic call to Lois: bureaucracy.

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In Issue #4 though, an impossible race against The Flash turns out to be the least of Superman's problems. Following a gruelling marathon against the (second) Fastest Man Alive, a lightning bolt splits Clark Kent and Kal-El in two. Kal's Kryptonian logic encounters the true power of Clark's human spirit. With two issues still to come, it's going to be challenging for Tom King and Andy Kubert to find a battle that lives up to this one. This isn't a physical fight, because everyone knows that's no contest. Instead, this is a philosophical one.

At first, Clark seems like the obvious victim here. He's unable to hunt for his own food, incapable of building his own shelter on a desolate alien planet, and of course, unable to fly away. But there's one advantage Clark does have. And Kal-El inadvertently admits it in so many words while he's slaying a gigantic space mammoth for Clark's dinner: "The human's capacity for self-knowledge is an evolutionary advantage. That marks him as more worthy of survival in this case."

Though he acknowledges Clark's worthiness from the outset, the logical Kryptonian half of Superman sees the futility of their odyssey. "I cannot save this girl," he says. And there it is again: "I can't," from that last line of code in the zeta beam that lingered. But Clark counters with something beyond logic.

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Clark's rebuttal reminds us, and the other half of himself, just what it means to be Superman. Superman is not one-dimensional. If he simply relied on logic and his irrefutable might, he would be no better than Brainiac. This clash, the culmination of all the challenges Superman has faced in the story so far, reinforces the fact that even though Superman is an alien, it is his humanity and indomitable spirit that makes him a hero.

Clark proves that no amount of logic can stand up to the willpower and determination of a noble man on a righteous mission. And in the end, cold logic must give way to humanity, because Superman's unbelievable power is secondary to his unwavering spirit. To Clark Kent, the words, "I can't" do not exist.

So far, Superman: Up in the Sky has pitted Superman against impossible foes and insurmountable challenges in every instalment. And for once, he's not the Godlike being in a cape who swoops in and saves the day. He's the underdog in a race against time to save an innocent life. And as Clark and Superman make peace and fly off together to find Alice at the end of this issue, the odds against them are zero to none. But in spite of that, there's still hope.

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