Spoiler Warning: Major spoilers ahead for all movies from Marvel Studios thus far

Five down. One more to go. That's the count when it comes to the Infinity Stones in the Marvel Cinematic Universe as of "Doctor Strange." Following the "Avengers: Age of Ultron" mid-credits scene where we saw Thanos wielding an Infinity Gauntlet, fed up with his minions' screw-ups, it became clear that the countdown began with the Mad Titan undertaking the hunt for them himself.

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The ones that are accounted for are the Space Stone, also known as the "Tesseract," (currently on Asgard), the Mind Stone (in Vision's forehead on Earth), the Reality Stone or "Aether" (with the Collector), the Power Stone (with the Nova Corps on Xandar) and lastly, the Time Stone (in the Eye of Agamotto on Earth). The big question remains: where could the Soul Stone be? With "Guardians of the Galaxy Vol. 2" and "Thor: Ragnarok" coming next year, let's assess the potential hotspots where it may be hiding!

15 On Ego

Kevin Fiege has already stated that Phase Three will see the remaining stones revealed and, while James Gunn has been downplaying rumors left, right and center, it would still be unwise to rule out the Soul Stone appearing in the "Guardians" sequel in May, 2017. Its cosmic scope is one of grandeur and the predecessor was the Marvel film that had the most exposition from Thanos, played by Josh Brolin.

That said, could the Soul Stone be the engine of power for Star-Lord's father, Ego? That character, also known as "the living planet" in the books, will be played by Kurt Russell, so we're expecting fireworks from the action star when the superheroes or villains meet him up. There's no bigger, better place to hide such a valuable item than there and whoever wants it will surely have to be able and willing to put up an epic fight! Even good ole' junior, but that's life in the MCU!

14 Where The Wild Gladiators Are

"Thor: Ragnarok" will be hitting the big screens in November 2017 and following that mid-credits scene that showed him talking to Stephen Strange, the hype's already started rolling. With Asgard already housing the Tesseract, having a hell of a cleanup campaign due to Loki's antics with the Mind Stone and lastly, palming off the Aether in space, it could be viewed as severe overkill to tie it to the "Thor" franchise again.

However, with Thor set to rumble with Hulk off-planet in an arena meant for the meanest gladiators of them all, one must wonder if this rough take on "Planet Hulk" could offer a foreign route to the missing stone. There's still a strong sense of mystery as to where Taika Waititi will have the duo duking it out, with whom, and also why, but what better place to hide such an asset than somewhere cloaked with secrecy. Or perhaps on another planet the Norse god encounters in his galactic road trip?

13 With Hela

It's very likely the MCU will be retconning Hela (played by the ever-impressive Cate Blanchett) because having her as Loki's daughter, Hel, could prove to be a tricky elaboration. To make her a truly intimidating power player in the third "Thor" film, though, one potentially major plot twist may well be that she has the Soul Stone. It could also tie into Thor's vision in the "Avengers" sequel where the dead taunted the Odinson in the first of a series of cosmic visions heralding Thanos' impending arrival.

Some rumors even posited that Hela could be turned into Thanos' version of Lady Death, which comic fans can tell you is one very cryptic yet engaging relationship. As complex as Hela can be at times with her schemes, storing the Stone could be a simpler way of adding her to the bigger picture without convoluting much. It would also offer Thanos an ally when he's ready to collect what Asgard is keeping from him.

12 Wakanda

Many have assumed that the Stone will be revealed next year, but with "Black Panther" preceding "Avengers: Infinity War" in 2018, Ryan Coogler could unveil a surprise in his directorial debut. It would also allow Marvel Studios more than enough time to draw out the saga of the Stones and tease the hell out of us, as cruel as that may be.

With T'Challa's origins still to be shown, we should remember that, in the rite of passage followed by the person chosen to don the mantle of the Black Panther, said chosen one has to meet the Panther God. Also highlighted in the comics was the selectee communicating with the spirits of the former Black Panthers. Could the MCU interpret this as meeting the souls of his ancestors? Either way, this would be the ideal spot to further marry how science and mysticism meets yet again to birth the new world-power that Wakanda has been revealed to be.

11 Attilan

"Agents of SHIELD" stunned fans and brought the Inhumans to television despite a film being slated by Marvel Studios. While the movie has been placed on the shelf for now, ABC proceeded to run riot with their Inhuman arc which, as fun as it is, doesn't seem like it could fit into the MCU. However, all it takes is Thor and Banner getting lost and rummaging through the remains of a fallen kingdom on the moon to find that another dynasty existed before.

It could offer hope for a prequel that ends on the demise of Black Bolt and his royal family or something that leaves room for the future arrival from Medusa, Karnak and posse. All that's really needed is a little snippet or tease like they did with Wakanda in the past movies. With so much priority given to Inhumans in modern Marvel comics, this would be a perfect introduction to film fans. After all, we're all waiting to see Blackagar on the throne ready to destroy with a whisper, even if in a flashback.

10 Atlantis

Let's be honest: to spit hot fire like Namor does, you've got to have had some experience in theater right? Fun aside, wouldn't it be dandy if the Stone was lodged in his underwater kingdom? We know how devilishly regal he is and fans have clamored for his intro over and over again only to be stopped dead in their tracks by complications due to ownership rights. Maybe though, this arc and a potential Illuminati tease for the long-term future could see the Sub-Mariner brought to life on-screen.

It's a longshot, but after Marvel partnered with Sony over Spider-Man, maybe something could be hot-wired to bring the Atlanteans into the fold? Just imagine the ruins of an underwater empire housing the Soul Stone: it would make for majestic cinema. Namor's arrogance and charisma alone begs for this dream to become a reality. Plus, it allows the MCU to take a stab at at what James Wan does with "Aquaman."

9 Mephisto's Lair

Just because the supernatural nightmare of a villain is being mentioned on "Agents of SHIELD," that doesn't mean he's going to be used strictly there. We're hoping they show him on the MCU because "Doctor Strange" has opened the door to so many possibilities in terms of mystical madness. Of course, he could even end up locking horns with a certain wall-crawler, although that seems highly unlikely.

The point is that there's always room for Mephisto and, while it may seem like shoehorning him in here, he's someone who could finally bring a credible threat to the rogues gallery from Marvel Studios. He's all about souls and bargaining, as we saw in "One More Day" and thereafter: so while it's a long shot, it's still one to take. Mephisto would be a spot-on choice to safeguard the Soul Stone. One that wreaks havoc and spills terror at every turn but a great one, nonetheless. This could also up the scare factor which Dormammu failed to deliver.

8 The Dark Dimension

Dormammu delivered quite an underwhelming finale in "Doctor Strange" but a key thing we learnt was the Ancient One fed off his energy from the Dark Dimension to remain immortal. Another big point made was that in this dimension, people are given the illusion of everlasting life. Could this immortality really be trapped souls? Seems like a stretch, but it would explain how powerful he is in that realm and just why he cannot be physically destroyed.

We're hoping that, since we know we haven't seen the last of him, and since Wong is joining Strange in "Infinity War," maybe they could journey into the abyss together to find an important piece of the puzzle. It'd also be interesting to see Thanos go there in search of the Stone, because either way, his presence there would lead to one heck of a fight between he and Dormammu. Most of all, we need to pump some more space cred into the Dark Dimension.

7 Kamar-Taj

"Doctor Strange" showed that the Time Stone and Eye of Agamotto are safe and sound back in Kamar-Taj. Honestly speaking though, why can't there be another stone stored there, hidden away with the Book of the Vishanti or even with Jericho Drumm? Not to mention there are three sanctums with artifacts and relics that contain as much power as they do mystery. We really don't know exactly what's hidden there and are betting its revelations would surprise Strange and Wong equally. After all, the Ancient One did keep a lot of secrets.

Out of everyone who found or became associated with a Stone, Strange's posse seems to be the ones who know most about handling with care and also, appear to be aware of the true strength inside so it'd make sense if they're doubling up, it's on this franchise. Asgard seems so easy to invade or sneak into in any case so we think these stranger places would be the more appropriate safe houses. It also leaves room for Vision and Stark to make a move or even that Illuminati boy band we mentioned.

6 In Thanos' Hands

Thanos had the Mind Stone and recklessly charged it to Loki to grab the Tesseract in "Avengers." We all know how that worked out for him. It would be quite a twist if he was also harboring one more and that he just didn't trust anybody else with it. It could also be something that gives him his strength or is simply used by him as a powerful back-up for when he goes treasure hunting.

Everybody's busy looking in one direction, but have any of us stopped to consider what Thanos must have been up to during all his off-screen time? Misdirection (making us think the only gem he has is the one given to Loki) is a hell of a thing and if anyone knows how to play these kinds of cerebral games, it's him. It could even be that the only reason he's referred to as "the Mad Titan" is the stone is because the Soul Stone is the source of his power, allowing him to dominate and rule so much of the galaxy. So many questions are posed and so few answers are forthcoming, but with everyone running around searching, Thanos hiding it in his back pocket makes sense because who'd expect the MCU to head in such a new direction?

5 Hidden By Tony Stark

Vision mentioned in "Age of Ultron" how much he's yet to learn with his Mind Stone. What if, in the process of trying to uncover the truth about his own Stone, he also learns about the Soul Stone and proceeds to recover it between films? Fetching it for Iron Man wouldn't be unbelievable given how Vision's shown he agrees with the shots being called by Stark right now. It's something made even easier if it's in an unguarded location like a tomb or a vault known for its impregnability, because he could simply change his body's density to slip inside undisturbed.

Alongside Vision, there's a lot of wisdom, local and otherworldly, to be explored by Tony Stark, so advancing their story like this would make for a fantastic revelation. It also lends to the ego and overprotective nature that we associate with Tony from "Civil War" in the movies as well as in the comics. That need for control, especially when coupled with how grief over his parents' deaths is often shown as one of his driving forces, could potentially lead to some interesting uses of the Soul Stone. We can already envision him digging in trying to find his parents' souls.

4 Oscorp Head Office

Marvel Studios and Sony have made this film together but to insert something of such magnitude like the Soul Stone doesn't seem like it would fit the grounded universe of Spider-Man. At first glance, that is. This Avenger has always had a diverse array of villains to battle and while "Spider-Man: Homecoming" is looking to the likes of the Vulture and Shocker, you never know if Norman Osborn is keeping something he cannot comprehend within his grasp. It would match up with the ambition he's shown in the comics, because his greed is constantly growing and so to is his thirst for knowledge.

If not shown in the Sony film itself, Marvel Studios could always borrow Spider-Man and Oscorp for a few scenes that show the web-slinger wrestling with Osborn, indirectly leading to the revelation that Oscorp has the Stone all along. Spidey seeing Uncle Ben's soul because of the gem would make for a powerful scene.

3 The Cancerverse

If you were a fan of Dan Abnett and Andy Lanning's Marvel cosmic material, then you know where we are heading. Not only would storing the Stone here be the ultimate place to keep it out of reach, but also if the MCU decides to push the boundaries, then this is where we can extract the likes of Adam Warlock and Richard Rider (the hero known as Nova) and finally throw them into the cinematic mix.

The Cancerverse is a deathless reality existing inside The Fault, a rift created in the comics stemming from a series of galactic battles. It was the result of events catalyzed by the "War of Kings" involving the Inhumans, Kree and Shi'ar among others and tied into quite a few cosmic entities, including Thanos. This could be a second chance to do a dark dimension that also acts as a scary reflection. Traversing here would be such a daunting task, but we can already see Star-Lord's team signing up for the job.

2 At The Quill Home On Earth

Peter Quill, aka Star-Lord, has endured a lot in the MCU, including never knowing his dad, losing his mother, being abducted, and getting indoctrinated into the art of being a space rogue. He persevered and ended up leading the "Guardians Of The Galaxy," all the while his connection to his mom and Earth remaining. With Ego being revealed as the dad who left him while he was so young, could it be that safety measures were taken in the form of his mother's engagement or wedding ring? Instead of a diamond, it could be a smart place to store the Soul Stone.

The answer could rope in the Guardians (and their haters) back to Earth and may even further explore Quill's already mysterious heritage. Using the gem as an engagement gift may seem like a stretch, but such a move would be unexpected and sentimental, which pretty much sum up Quill and the first Guardians film as a whole anyway.

 

1 With Howard The Duck

He's a duck, he likes getting wasted, and it seems The Collector trusts him enough to share a drink with him, so why not have him hiding the Soul Stone somewhere in his apartment during the sequel? The point is that James Gunn usually has a motive for everything, so introducing Howard into the MCU may be part of a bigger machine than just fan service. Could there be something more that adds importance to Howard?

If The Collector did slip him something for safekeeping, then it's definitely because he would have thought that Howard would make for the least likely place hunters would think to look for it. This scheme may seem stupid, but it does have an air of genius to it because of how Howard just does not stack up as someone who you'd assume might be hiding something as extremely powerful and important as the Soul Stone.

Digging our hiding spots? Conspiracy theorists, sound off in the comments!