The big plot thread running through almost all the Marvel Cinematic Universe films since the beginning has been the introduction of the Infinity Stones. Each of these powerful artifacts, all dating back to the dawn of time, has the ability to control a different property in the known universe. In the pages of the classic Marvel Comics, the stones (there called the Infinity Gems) were combined together by the mad Titan Thanos (Josh Brolin in the films), who placed them all on his Infinity Gauntlet, which in turn made him the most powerful being in the universe. This story ran through the epic Infinity Gauntlet mini-series years ago, and will serve as the basis of next year’s Avengers: Infinity War.

There are six Infinity Stones all together, although so far over the course of 14 Marvel Cinematic Universe films, we have only been introduced to five of them. Here is a primer for Marvel fans to get caught up one each of the Infinity Stones–i.e., which film they first appeared in and where they are now–before Thanos gets his greedy, evil paws on them.

The Space Stone / The Tesseract

The Tesseract was properly introduced in 2011’s Captain America: The First Avenger, and was used in Loki’s (Tom Hiddleston) invasion of Earth in The Avengers the following year. In the comics, the Tesseract is the Cosmic Cube, a separate totem of power from the Space Stone, but in the MCU these two items are combined. The Tesseract allows its controller the power over space, like creating portals from one part of the cosmos to the other.Originally guarded by the Asgardian King Odin (Anthony Hopkins), it ended up going missing on Earth thousands of years ago. It was then discovered during the second World War by HYDRA (that’s where it came into play in the plot of Captain America: The First Avenger), until they were defeated, and the Tesseract ended up in the keep of S.H.I.E.L.D.

Decades later, S.H.I.E.L.D. director Nick Fury (Samuel L. Jackson), secretly tried to use the Tesseract in the creation of a new class of energy-based weapons. Loki then stole it from S.H.I.E.L.D. and used to it open a portal through space, which brought his alien army the Chitauri to invade the Earth. This invasion was of course stopped by the Avengers in their first big screen outing; afterwards, Thor returned the Tesseract to Asgard, where it resides once again in Odin’s vault.

Last Seen: Being taken by Thor back to Asgard, at the end of 2012’s The Avengers.

The Aether / The Reality Stone

The Aether, a.k.a. the Reality Stone, was first seen in Thor: The Dark World, and although it is technically an Infinity “Stone,” we see it almost only in its liquid state. What its exact power is remains unknown, but it was almost used to physically alter the nature of reality itself. In its film debut, the lord of the Dark Elves known as Malekith (Christopher Eccleston), tried to use it to snuff out all light in the universe. Bor, Thor’s grandfather, put a stop to him and took possession of the Aether, and hid it away on a secret planet.

There it stayed dormant until the events of The Dark World. Once they got it back, Thor and the Asgardians had to decide where to safely hide it, as it was recognized that having two Infinity Stones kept in such close quarters would render too easy a target. The Asgardians decided to turn it over to The Collector (Benicio del Toro) in the end credits tag of The Dark World… which might have been a really dumb idea. Once the Collector has one stone, it’s only a matter of time before he’ll want the other five.

Last Seen: Going into the Collector’s vast collection, in the end credits tag after 2013’s The Dark World.

The Orb / The Power Stone

This stone was first seen in Guardians of the Galaxy, when intergalactic pirate Star-Lord (Chris Pratt) procured the Orb in an ancient temple on the long dead planet Morag. He was hoping to sell it and make a quick buck, not realizing what it truly was. Over the course of Guardians of the Galaxy, Star-Lord and the team learned the real backstory of the Orb–that it was the ancient Power Stone which would grant unlimited destructive capabilities to its owner, enough to destroy an entire planet. After safely keeping it out of the hands of the villainous Ronan the Accuser, the Guardians handed off the Power Stone to the Nova Corps, the most prestigious police force of the galaxy, who reside on the planet Xandar.

Last Seen: In the custody of the Nova Corps on Xandar at the end of 2014’s Guardians of the Galaxy.

The Mind Stone

This one actually also made its debut back in the original Avengers film, only we didn’t know that it was the Mind Stone at the time. In that movie, Loki was given a powerful scepter by Thanos, one that can control the minds of others, in his efforts to conquer Earth. We then learned in Avengers: Age of Ultron that Loki’s scepter actually housed the Mind Stone, which was why the Asgardian trickster god was able to use it to brainwash and mind control whomever he chose.

Eventually, the mind stone is freed from the scepter, which had fallen into the hands of HYDRA, and was used in the creation of a powerful sentient android that had the stone embedded on his forehead. That android, going by the name the Vision (Paul Bettany), helped the Avengers defeat their robot nemesis in Avengers: Age of Ultron, ultimately becoming an Avenger himself.

via GIPHY

Last Seen: In 2016’s Captain America: Civil War, still resting in the body of the Vision.

The Eye of Agamotto / The Time Stone

via GIPHY

In last year’s Doctor Strange, we learn that for centuries, the Earth has been protected from mystical threats by the Sorcerers Supreme. The first of these powerful magic users was known as Agamotto, and when he acquired the ancient artifact known as the Time Stone (which allows one to control the flow of the space-time continuum), he placed the emerald gem inside a pendant, which then became known as the Eye of Agamotto.

The Eye was then kept hidden and safe inside the ancient library of Kamar-Taj, home of the Masters of the Mystic Arts. Doctor Stephen Strange was able to use the Time Stone to defeat the dark lord Dormammu from conquering our dimension.

Last Seen: Safe in the hands of the Masters of the Mystic Arts, at the end of 2016’s Doctor Strange.

The Soul Stone

This one has yet to make its film debut, but expect it to show up in either Guardians of the Galaxy: Volume 2, or in Thor: Ragnarok this year. In the original Marvel Comics, the Soul Stone was able to control the souls of any being, alive or dead, as well as transport its owner to the afterlife. It remains to be seen if the Soul Stone will have the same powers in the Marvel Cinematic Universe.

Are you ready now for the big cosmic battle of Avengers: Infinity War? And which film do you think the next Infinity Stone will turn up in? Let us know your thoughts down below in the comments.

Images: Marvel Studios

What is Thor: Ragnarok‘s Infinity Stone connection?

[brightcove video_id=”5396289801001″ brightcove_account_id=”3653334524001″ brightcove_player_id=”rJs2ZD8x”]