Veritable comic book icon Alex Ross has alerted fans to a Superman reference they may have missed in one of the artist's most celebrated works, Kingdom Come. Ross took to Twitter and posted a side-by-side comparison of Superman: one from a scene in Kingdome Come, another from one of Superman's earliest comics. Fans were open-mouthed once they realized they had overlooked a subtle homage to one of the Man of Steel's most classic covers!

Kingdom Come is a four-issue miniseries from Mark Waid and Alex Ross that was released in 1996. The series is set in an alternate future where the beloved heroes of the DC Universe have gotten older and a new generation of vigilantes has arisen. With the new crop having more radical ideas on fighting crime than their predecessors, an ideological rift threatens to tear the superhero community apart as nuclear war looms. Kingdom Come was highly lauded by critics and fans who regard it as one of the best superhero stories of all time.

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Kingdom Come is a story filled to the brim with references to DC's decades-long history. Some are plain as day, but others are so sly, readers had no clue until one of the books co-creators pointed it out. On Twitter, Alex Ross posted an image of Clark Kent from Kingdome Come #1, which shows Clark Kent repairing a barn while hoisting a beam of wood with one arm. The artist also posted an image of the cover of 1939's Superman #1 by Joe Shuster. Ross' followers had to do a double take at the realization that the images had the exact same pose. Though Ross said nothing in response to fans, the homage speaks for itself when shown side by side with the original.

Though it seems obvious when laid out next to one another, fans couldn't believe that they had glossed over the reference. Ross' post received thousands of likes and a number of awe-struck comments from fans who were kicking themselves for never noticing. Nightwing artist Bruno Redondo even admitted he never connected the dots, saying in a response, "I can’t believe I didn’t notice, and it’s just PERFECT. Always learning from you."

Superman is one of the oldest superheroes in the comic book world and many of his earliest appearances are etched into the minds of comic book fans. Superman slamming a car on the cover of Action Comics #1 or breaking out of a chain binding for Superman #11 serve as iconic images that have been honored by many creators throughout the years. Kingdom Come's Easter egg isn't simply a coy reference, it's a tribute to the longtime legacy of the Man of Steel. While Superman fans may have initially missed Kingdom Come's tribute before, they can certainly appreciate it now thanks to Alex Ross.

Next: Kingdom Come Writer's Favorite Superman Moment Isn't From Comics

Source: Alex Ross