The trailers have been released, the TV spots are beginning to proliferate (featuring even more never-before-seen footage), and the film itself is five short weeks away from debuting in theaters to what will undoubtedly be record-breaking box office numbers. And yet while we know so much about Avengers: Age of Ultron, Marvel’s insanely anticipated sequel to 2012’s $1.5 billion-grossing superhero team-up, we know very little about the newest addition to its costumed roster—namely, the Vision.

Which isn’t to say there isn’t considerable speculation about this most mysterious of characters to make the leap from the comic book pages to the Marvel Cinematic Universe (MCU). However, though he was briefly spied—in the form of a close-up of his eyes—at the end of the latest Ultron trailer, there’s little substantive information about the movie version of Vision, why he’s being played by Paul Bettany (who’s previously voiced Tony Stark’s A.I. computer J.A.R.V.I.S. in the Iron Man films), and how he’ll fit into Joss Whedon’s sequel, which concerns the Avengers’ battle against a sentient robot named Ultron (voiced by James Spader) who’s created by Stark to protect Earth, but goes rogue and opts to destroy humanity—and the heroes—instead.

If Whedon hasn’t divulged anything concrete about Vision, a look to the character’s comic book backstory offers tantalizing clues as to the possible role he’ll play in this summer’s film.

The Vision first appeared in October 1968’s Avengers #57 courtesy of Ultron, an evil robot designed by Avengers member Hank Pym (aka Ant-Man) who rebelled against his creator and sought to destroy the superhero team. Ultron’s hatred of Pym—and love for Pym’s wife, Janet van Dyne (aka The Wasp)—revealed him to be an automaton with severe daddy issues. Determined to defeat his nominal father, Ultron took the body of the original android Human Torch (or, more specifically, a replica of that body), gave it a green color to go along with a red face (and a nice yellow cape and pair of boots and gloves), gave it the mind of the dead Wonder Man, implanted him with a “control crystal,” and sent this being to kill the Avengers.

Upon seeing this creature, the Wasp referred to him as “an unearthly, inhuman vision,” and thus the Vision was properly born. Imbued with the ability to fly, to blast energy beams from his eyes and his forehead crystal, and to alter his body’s density (thus allowing him to become super-strong, or so ghostly that he can pass through physical objects), the Vision was a formidable Avengers adversary—at least, until that “control crystal” proved to be a terrible fail-safe for Ultron, and the Vision was convinced by the Avengers to become a turncoat and join their side. Embraced as their newest team member, the Vision helped the Avengers defeat his maker. Yet in a bizarre turn of events that makes little sense (except in the comic book world, where outlandish soap opera-y twists are often the norm), the Vision temporarily lost control of himself and rebuilt Ultron out of adamantium—the unbreakable metal alloy that was also used for Wolverine’s skeleton and claws. This horrible decision led to another battle with the robot villain, during which the Vision again helped his comrades fell his former master.

In the ensuing years, the “synthezoid” Vision’s humanity became more pronounced. That was most clear with regards to his romantic relationship with mutant beauty Wanda Maximoff (aka the Scarlett Witch), which resulted in marriage, even though the Vision was only human from a psychological standpoint. While the Vision’s artificial construction should have been a marital (and, ahem, intimacy) hindrance, the Scarlett Witch—herself possessing all sorts of formidable powers—cast a spell that allowed the couple to procreate, and soon they had two sons, Thomas and William. Or so they thought, until it turned out that the boys were really just parts of the villainous Mephisto’s fractured soul, and were subsequently absorbed back into Mephisto. That so upset the Scarlett Witch that it drove a wedge between her and the Vision, and they eventually divorced. Alone, the Vision would set off on further Avengers adventures of an increasingly convoluted sort, many of which involved him being blown up and put back together again like a superpowered latter-day Humpty Dumpty.

What does all of this mean for Avengers: Age of Ultron? Whedon’s follow-up story will not only introduce the Vision but also the Scarlett Witch (played by Elizabeth Olson), though save for some potential third-act foreshadowing, it’s difficult to believe the already overstuffed film would have any room to develop the duo’s romance. Still, it’s more than likely that Vision’s comic book origins will play out in relatively faithful fashion in Whedon’s saga, with only some minor alterations at play.

Without question, those changes will involve Ultron, since in the comics, he’s designed by Ant-Man—who’s not appearing in Avengers: Age of Ultron, since he’ll be busy headlining his own solo feature this July 17 (starring Paul Rudd). Instead, it’ll be Robert Downey Jr.’s Tony Stark who invents Ultron. Thus it’s probable that when Ultron creates Vision, he’ll do so via Stark’s technological hardware and software—which, in the movies, is controlled by J.A.R.V.I.S. (voiced by Paul Bettany). That’s almost surely why Bettany is embodying the Vision; he’s being reimagined as the physical manifestation of Stark’s A.I. computer, with superpowers comparable to Iron Man’s (namely, similar flight and energy-beam capabilities). From there, it’s not hard to envision an Ultron finale in which the Avengers find themselves overwhelmed by Ultron’s robot-army onslaught, and snatch triumph from the jaws of annihilation only by convincing Ultron’s ultimate weapon—Vision—to see the value in saving humanity, and to switch allegiances and aid them in their cause.

Admittedly, that’s just speculation at this point. But between clues gathered from casting choices, trailers, and the character’s comic book beginnings, it’s becoming easier to imagine that sort of source material-faithful scenario playing out. For all of its iconic do-gooders, come May 3, Age of Ultron’s ultimate hero may just be the one we’ve yet to even properly see.