Marvel Comics has teased the conclusion -- long thought to be a cliffhanger -- from the final chapter of the acclaimed comic book mini-series and crossover, "Spider-Men."

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Back in 2012, Peter Parker from Marvel’s 616 universe finally met with the relatively new, but already much loved, Miles Morales version of Ultimate Spider-Man. In “Spider-Men,” the two heroes met, fought, became friends, and teamed up against the villain Mysterio, who had opened up a gateway between the two dimensions.

Critics and fans alike praised “Spider-Men," as readers got a crossover that felt heartfelt and genuine as it touched on themes and emotions important to the Spider-Man mythos. Some of it was very much fan-service, as interactions unfolded that readers were interested in seeing; an older Peter Parker reunited with Gwen Stacy (who had died in his universe years earlier), and Aunt May got to see her nephew all grown up (after he died not too long ago in her universe at a young age).

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At the end of the mini-series, with both heroes returned to their respective universes, Peter Parker decided to check on Google whether there was a Miles Morales in his universe, just as there was another Peter Parker over in the Ultimate universe. 616 Peter’s findings leave him shocked, as his jaw all-but drops to the floor. However, readers never learned what had left Peter stunned.

For years, readers thought it would just be an unsolved mystery in comics; something lost to time that would never be looked back on. As it turns out, Marvel had not forgotten, and they are ready to finally address the big reveal we never saw.

Coming soon from Marvel Comics... pic.twitter.com/MqtmHMU1Qi— Marvel Entertainment (@Marvel) April 14, 2017

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Other than promising a sequel, the teaser for the series -- that will presumably be called "Spider-Men II" -- doesn't reveal the creative team or other pertinent details. Stay tuned to CBR as more information is revealed.