SPOILER WARNING: This article contains spoilers for "Doctor Strange," in theaters now.


In addition to character cameos and shout outs to the events of other movies, there's one major thing uniting all the disparate Marvel Studios films: the Infinity Stones. The six all-powerful stones (originally known as gems in the Marvel comics) have popped up in nine of the franchise's fourteen films, movies ranging in scope and tone from the World War II period piece "Captain America: The First Avenger" to the outer space adventure film "Guardians of the Galaxy." These stones -- remnants of six singularities that existed before the Big Bang molded into stone form -- are everywhere, and theorizing about their whereabouts has become a favorite pastime of Marvel Cinematic Universe fans.

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With the release of "Doctor Strange," the fifth Infinity Stone has been identified, leaving just one more out there somewhere in the multiverse just waiting to be found. And that stone will be found; Thanos, the big cosmic-level bad that's been lurking in the shadows ever since 2012's "Avengers," is on the hunt for all six so he can achieve ultimate power. Considering that the next Avengers film is subtitled "Infinity War," odds are we're going to see the last stone before then. But what about the five other stones? When did we see them, and where are they now? Here's an update on the Infinity hunt.

Space Stone

space-stone

  • Color: Blue
  • Seen In: "Thor" (2011), "Captain America: The First Avenger" (2011), "Marvel's The Avengers" (2012)

The very first Infinity Stone audiences saw was encased in the Tesseract cube, which was glimpsed in the post-credits scene of 2011's "Thor." The cube was then seen in flashback in "Captain America: The First Avenger," where it was used by the Red Skull to power Nazi and Hydra weaponry with blue energy blasts that seemingly disintegrated their targets. It's more likely, however, that the victims were sucked into a different dimension, as it was revealed that the Tesseract was in fact the Space Stone. That stone was then used in 2012's "The Avengers" to open up a wormhole over New York City. After defeating Loki and the Tesseract, the Avengers handed the item (including the Space Stone) over to Thor for safekeeping in Asgard. The Space Stone is currently in Asgard.

Mind Stone

mind-stone

  • Color: Yellow
  • Seen In: "Marvel's The Avengers" (2012), "Captain America: The Winter Soldier" (2014), "Avengers: Age of Ultron" (2015), "Captain America: Civil War" (2016)

Appearing in the most movies of any stone, the Mind Stone has had an interesting journey so far. The Mind Stone was previously the one stone in Thanos' possession; the Mad Titan gave the stone, embedded in a scepter, to Loki for the God of Lies to use in his conquest of Earth. Loki used the scepter and Mind Stone to brainwash people to do his bidding, including Hawkeye and Dr. Erik Selvig. When the Avengers defeated Loki, the scepter ended up at S.H.I.E.L.D. -- which in turn ended up in the hands of Hydra, the evil organization that had infiltrated and corrupted S.H.I.E.L.D. The post-credits scene of "Winter Soldier" shows that Baron Wolfgang von Strucker was using the scepter and stone to experiment on humans; two of his test subjects, Pietro Maximoff and Wanda Maximoff, received super powers as a result of these experiments. The scepter was recovered by the Avengers during their raid on von Strucker's base, and it made its way back to Stark Tower. The Mind Stone then ended up being placed on the synthetic being Vision's forehead, thus giving him a mind of his own. The Mind Stone is currently on the Vision's forehead, residing in the Avengers' compound.

Reality Stone

reality-stone

  • Color: Red
  • Seen In: "Thor: The Dark World" (2013)

Referred to as a weapon called the Aether, the world-warping Reality Stone was originally a weapon used thousands of years ago in the realm of Svartalfheim, but the Asgardian Bor (grandfather of Thor) stopped its usage and hid it away in a faraway realm. The Dark Elf Malekith found the Aether in the present day and tried to use it to destroy all Nine Realms (including Earth and Asgard) during a cosmic event called a Convergence. Thor prevented Malekith from accomplishing his goal. Thor recovered the Aether and, wishing to keep it away from the Tesseract in their possession, sent the powerful weapon deep into outer space where it would join the collection of the aptly named Collector. Later, the Collector's outpost would be partially destroyed by a burst of energy from the Power Stone. Despite that, it's still assumed that the Reality Stone is still in the Collector's possession within the floating Knowhere outpost deep in space.

Power Stone

power-stone

  • Color: Purple
  • Seen In: "Guardians of the Galaxy" (2014)

The Power Stone was the object that a number of scoundrels and despots sought in "Guardians of the Galaxy." Initially, the stone was hidden in a temple on the abandoned planet of Morag, which is where Peter Quill -- a.k.a. Star-Lord -- found it. He ran afoul of Ronan the Accuser's Kree warriors; they also sought the orb containing the Power Stone, as it would eventually go Ronan's boss Thanos. Star-Lord made off with the orb as he and a ragtag group of criminals made their way to the Collector on Knowhere. There, they saw the Power Stone within the orb and experienced its power as it exploded, nearly destroying the Collector's entire base. After witnessing the stone's power, Quill and his team fought to keep it out of the hands of Ronan. This culminated in a final showdown wherein the newly named Guardians of the Galaxy united to contain the stone's energy and utterly destroyed Ronan. They then turned over the orb containing the Power Stone to the Nova Corps, an intergalactic peacekeeping agency. The Power Stone is located in a highly protected safe on the Nova Corps homeworld of Xandar.

Time Stone

time-stone

  • Color: Green
  • Seen In: "Doctor Strange" (2016)

And this right here is the latest addition to the collection. In "Doctor Strange," injured surgeon Stephen Strange seeks mystical help to heal his broken hands in the hopes of getting his old career back. Instead, he takes to the mystic arts and during his studies, comes across an ancient artifact known as the Eye of Agamotto. Strange discovers that the artifact, when opened, allows him to manipulate time, dialing it forward and backwards as if by remote control. Wong, the resident librarian within the Ancient One's Kamar-Taj training facility, casually mentions that the Eye of Agamotto contains an Infinity Stone and should not be messed with. Later in the film, Strange uses the Eye of Agamotto and the Time Stone in a one-on-one confrontation with the Dread Dormammu of the Dark Dimension. He traps the extra-dimensional entity in a time loop, exposing the timeless Dormammu to the oppressive trappings of time. Dormammu relents and leaves Earth alone. At the end of the film, Doctor Strange returns the Eye of Agamotto to it's resting place on a pedestal within the Ancient One's compound, as he has not yet learned how to completely master it. The Time Stone is currently in Kamar-Taj, just a portal trip away from Doctor Strange's Sanctum Sanctorum in New York City.

Soul Stone

infinity-stones

  • Color: Orange

And that just leaves one more stone -- the Soul Stone. It's location remains unknown, but Marvel Studios president Kevin Feige has been upfront about saying that we will most likely see it during Marvel's Phase Three slate of films.

"You will see the other two sometime in Phase Three, for sure," said Feige back in September 2015. "There’s a gauntlet that needs to be filled."

That hint has partly come to pass now that we know the Time Stone is in "Doctor Strange." The list of films it could appear in has also gotten shorter, as there are only a handful of Phase Three movies left before "Avengers: Infinity War" arrives in May 2018. Next up is "Guardians of the Galaxy vol. 2," which -- as a cosmic Marvel movie -- could introduce the Soul Stone as easily as the first "Guardians" did the Power Stone. Could the Soul Stone be what's powering Star-Lord's father, Ego? That character is also known as "the living planet" in the comics, so maybe this Ego needs a little bit of soul to come to life?

"Spider-Man: Homecoming" arrives in July 2017, and it's highly unlikely that the Soul Stone will pop up there. That film is set in a high school in Queens and features Peter Parker going up against the Vulture. It would be a bit odd to squeeze the Soul Stone in such a grounded film. November 2017's "Thor: Ragnarok" is a much more likely candidate, as that film will not only take place in the Norse realms but also across potentially multiple planets. Considering how many unearthly locations the film will contain, it'd make sense for the Soul Stone to pop up somewhere.

Then there are the 2018 Marvel movies. February of the year will see "Black Panther" hit theaters, and it's possible the Soul Stone is within Wakanda. After all, where better to place an all-powerful stone than within Wakanda's well-guarded borders? Lastly, there's always the chance it'll pop up in "Avengers: Infinity War," with Thanos' quest to catch'em all -- including the Soul Stone -- taking him on a tour of the entire Marvel Cinematic Universe.

Whether the final stone is revealed in "Guardians of the Galaxy vol. 2" or "Avengers: Infinity War," we still probably have to wait until 2018 to see Thanos finally put that empty Infinity Gauntlet to use.