'Agents of S.H.I.E.L.D.' Teases the Return of Graviton, a Season 1 Easter Egg Left Unexplored — Until Now

The second 'pod' of Agents of S.H.I.E.L.D. has come to an end, teasing a dramatic third arc that will plunge our heroes into a madhouse mirror world where Hydra rules! This arc is sure to reward long-term viewers, bringing the dead back to life and exposing characters' deepest, most intimate desires. But it seems Hydra isn't the only thing Marvel is bringing back to Agents of S.H.I.E.L.D....

In a wide-ranging interview with IGN, showrunner Jed Whedon and star Chloe Bennet dropped some fascinating teasers. Specifically, they focused in on a plot-element you could easily have forgotten: Gravitonium.

Agents of S.H.I.E.L.D. fans will remember the word from way back in the Season 1 episode "The Asset". We were introduced to Ian Hart's Doctor Franklin Hall, a brilliant scientist who'd become world-renowned for his work on an extremely rare element known as Gravitonium. Hall became an instructor for S.H.I.E.L.D., and was an instructor at the S.H.I.E.L.D. Academy; he actually taught Fitz and Simmons!

Tragically, in "The Asset", Hall's genius came back to haunt him. He learned that his old associate, Ian Quinn, was conducting dangerous experiments with Gravitonium; Hall launched an insane plan to stop him by turning the Gravitonium against him. In the end, S.H.I.E.L.D. was able to stop Hall's plan, but at a cost; he was plunged into a gravitational generator, and left trapped inside the Gravitonium. Neither S.H.I.E.L.D. nor Hydra realized this, and since then, that ball of Gravitonium has cropped up time and again — with no hint that Franklin Hall would ever escape.

Until now.

Is Graviton due to appear?

With an ever-increasing focus on superhumans, Agents of S.H.I.E.L.D. Season 4 looks set to bring Franklin Hall back into play. Jed Whedon told IGN:

"We would not be doing our jobs as well as we could if we left that unanswered."

It's a pretty clear hint, but it raises some intriguing possibilities. On the one hand, fans have been eagerly expecting Hall to escape the Gravitonium at some point; in the comics, he gained the ability to manipulate gravity and launched a career as a super-villain. Given that Agents of S.H.I.E.L.D. has regularly cast back to the Gravitonium, this would make sense.

As a series, though, Agents of S.H.I.E.L.D. loves to toy with audience expectations. With both Fitz and Simmons now inside the Framework, Franklin Hall's genius could be very, very useful to the S.H.I.E.L.D. team. Is it possible that it will be his intellect, not his super-powers, that lead to his playing a major role in Season 4?

There is another possibility, of course. In the upside-down world of the Framework, each characters' regrets have been undone — and Fitz surely regrets Hall's apparent death. It's possible that, in the Framework, Hall never died; while the Framework version of Fitz never joined S.H.I.E.L.D., perhaps in this twisted virtual reality Hall works with Fitz.

For now, this is just a tantalizing hint at what #Marvel has in store for us in "Agents of Hydra", the third arc in Agents of S.H.I.E.L.D. Season 4. This is truly a season that's going to reward long-term fans, drawing in plot threads that have been left dangling from as far back as 2013. It's going to be fascinating to see how this plays out!

(Source: IGN; Poll Image Credit: ABC)