Coming to theaters this December is the Michael Fassbender action/adventure vehicle Assassin’s Creed, the first trailer to which you can check out above. Chances are, you’ve at least heard of Assassin’s Creed, as the movie is based on a wildly popular, nine-year-old video game franchise. Created and published by Ubisoft, this best selling game series is being translated to the silver screen by the developer’s brand new proprietary movie studio, Ubisoft Motion Pictures.

The Assassin’s Creed universe is a vast place, with a mythology sprawling wide enough to stand alongside the likes of Game of Thrones or The Dark Tower. Characters and conflicts mingle with real-world history and genuine historical figures. There are two concurrent storylines unfolding in the modern day and across centuries past. Then there’s what the Assassins can do, such as their breathtaking free-running abilities and their trademark weapon, the Hidden Blade. And lurking behind all of it is a conspiracy dating back tens of thousands of years, to a civilization that came before mankind.

Understandably, getting your head around this world can be intimidating. So let us take you on a quick tour of the big stuff, the important things that are essential to understanding the world of Assassin’s Creed.

Templar/Assassin Conflict

For centuries, two secret societies have been engaged in an unending, hidden war. The Assassins are an order devoted to personal freedom, and enact capital punishment on the corrupt. They subscribe to the “kill one to save a thousand” mentality, and pride themselves on standing up for the innocent as part of the “Creed” they live by. The Templars believe in control above all else, and want to solve all of the world’s problems by maintaining complete command over the world and everyone in it. They work toward a “New World Order” free of war, disease, and poverty, which would be great except for that whole “loss of personal freedom” thing.

Both factions ultimately work toward the same end result — the betterment of mankind, and peace on Earth — but their ideologies put them in strong opposition. Across the Assassin’s Creed games, countless slices of real-world history have been shown or glimpsed in which the Assassin/Templar war has played a pivotal role behind the scenes.

The Templars and Assassins of the game series are actually based on a pair of real-world armies that originated during the Crusades. The Assassins are loosely based on the historical Hashashin, also known as the Nizari Ismailis. The Templars are a rough approximation of the Knights Templar, but a lot nastier.

The Animus

Central to the Assassin’s Creed series, despite its heavy focus on history, is a conflict in the here and now. In fact, it’s the modern representation of the Assassin/Templar war. Both sides in the war have developed a new technology that can allow anyone to access a virtual reality construct of something unprecedented.

It’s a device called the Animus, and it’s based on the notion that DNA holds not just genetic data, but the memories of one’s ancestors. Without these “genetic memories,” there would be no Assassin’s Creed. The original game in the series introduced the Animus, and as gaming technology has advanced over the years, the Animus in the game has continually been upgraded. Via the Animus, users can effectively experience the memories of any of their ancestors. But it doesn’t have to be one’s own ancestors; it can be those of anyone who’s had their DNA sequenced.

So why do it? What’s the purpose of going back into history, aside from the research and scientific applications? The Assassins used it as a training method in Assassin’s Creed II, and it looks like the same can be said of the movie adaptation. Michael Fassbender’s character Callum Lynch will reportedly gain Assassin skills from his Spanish ancestor Aguilar thanks to the Animus. But the Templars have a much more nefarious use for the device…

Major Characters

The first five (arguably six) games in the series featured a modern day protagonist named Desmond Miles. Desmond was born into the Assassins and trained as a child, but grew up and rebelled against the Order (and his family). Across those early games, he came to trust the Assassins and believe in their cause, fighting for them and even (spoiler alert) giving his life in the end, to save the world. More on that later.

Through Desmond’s genetic memories, we met a series of Assassins who lived long ago, each belonging to a different major era of history. The first game introduced Altair, a devout member of the first generation of Assassins, who operated in the Holy Land throughout the 12th Century A.D. Altair’s journey was one of redemption. after his arrogance caused a mistake that resulted in the lost lives of his Assassin brothers. Fan-favorite Ezio Auditore starred in Assassin’s Creed II, Assassin’s Creed: Brotherhood, and Assassin’s Creed: Revelations, which formed a trilogy. Ezio lived primarily in Italy during the Renaissance, and watching his cocky, romantic impulsiveness mature into a wise, seasoned warrior across the three games was immensely satisfying.

Ezio was followed by Connor Kenway in Assassin’s Creed III. Connor was a half British, half Native American Assassin in the burgeoning United States during the Revolutionary War. Though powerful and highly skilled, Connor proved unpopular with fans for his stoic demeanor — a stark contrast from Ezio. Connor was followed by a rewind to his own grandfather, the pirate Edward Kenway, in Assassin’s Creed IV: Black Flag. Edward’s was another quest for redemption, though a more satisfying one, as it famously “made a soldier out of a scoundrel.” His story involved a great deal of sailing the high seas, ship-to-ship warfare, and looting of Caribbean islands.

Each of these characters share a special sixth sense known as “Eagle Sense,” allowing them to see another level of reality. There have been several other protagonists in the series, but these are the characters players remember most. While none of them are expected to appear in the Assassin’s Creed movie, the movie shares continuity with the games, and Ubisoft has undoubtedly applied the lessons it learned from these characters in the creation of Aguilar, and his descendant Callum.

History

Although the modern day conflict is crucial to the series’ ongoing storyline, far more time in the games is spent experiencing its trademark, realistic recreations of historical locations. Sure, artistic license is employed when necessary — games are supposed to be fun, after all — but Ubisoft prides itself on the authenticity of its research into historical accuracy.

Using these carefully-chosen locations and time periods affects everything about the games. Assassin’s Creed: Brotherhood, for example, is set in early 16th Century Rome, giving the game a dry, brown, dusty atmosphere. The 18th Century Paris of Assassin’s Creed Unity is a wonderland of beauty, high culture, and vibrant colors.

Equally important to the locations have been their inhabitants, which in every game has included well-known historical figures. Ezio Auditore was friends with Leonardo da Vinci, and fought against the infamous Borgia family. Connor Kenway fought beside George Washington and Samuel Adams. Edward Kenway had pirate friends that included Benjamin Hornigold and Edward “Blackbeard” Thatch. The Frye twins of Assassin’s Creed Syndicate rubbed shoulders with Charles Dickens, Alexander Graham Bell, and Florence Nightingale.

It’s a safe bet that the movie(s?) will find Aguilar interacting with real-world individuals like these.

Abstergo Industries

As time marched on, both Templars and Assassins had to change to accommodate advances in society. While the Assassins continued to operate in secret, the Templars changed tactics in the early 20th Century. Abstergo Industries was founded as a front organization for the Templars, through which they could conduct commerce and trade based on scientific progress.

Abstergo’s most well-known invention is the Animus, but the company has its claws in multiple global industries. With unmistakably pointed social commentary, Ubisoft positions Abstergo as a world leader in pharmaceuticals, along with new technologies. One branch, Abstergo Entertainment, is a video game studio who created an in-world game that’s very much like Assassin’s Creed IV: Black Flag — the very game in which this faux developer appears! Their true purpose, of course, was to further influence the public at large.

Many of Abstergo’s exploits — along with so much Assassin’s Creed world-building and storytelling — have been revealed via tie-in media such as novels and comic books.

The Hidden Blade

Assassins use a wide range of weapons and tools, but none are more synonymous with Assassin’s Creed than the Hidden Blade. Accessed via a wrist gauntlet, the Hidden Blade is a retractable knife that can be easily concealed when not in use, and instantly accessible when needed. It’s a silent, fatal weapon used only in close-quarters combat and covert assassinations.

In the days of Altair, devotion to the Assassin Order was shown by removing the fourth finger, or “ring finger” of the Assassin. This allowed for the Hidden Blade to be released whether the user’s hand was open-palmed or clutching something. This practice was quickly retired, and later Assassins would wear not only a Hidden Blade on each wrist, but a number of variants on the original design.

For example, in Assassin’s Creed: Revelations, an older Ezio used a hooked blade to slide around Constantinople on ziplines. Arno Dorian used a variant blade that he could shoot at enemies using a tiny, built-in crossbow. Evie and Jacob Frye had Hidden Blades with fast-retracting grappling hooks attached that allowed them to scale buildings and traverse distances much faster than their ancestors. Other variations include poison-tipped blades and Hidden Guns that fire bullets.

Parkour

A big part of every Assassins set of abilities is the art of “freerunning,” or what we know today as Parkour. No obstacle is too big or too high to get between an Assassin and his prey, and Assassins are trained from an early age to become proficient at climbing and freerunning across any terrain.

It doesn’t matter if an Assassin is operating in a bustling city or a primitive forest, the majority of players’ movements typically unfold with the help of Parkour. It plays into combat as well, as a clever Assassin can use his or her surroundings or nearby objects against their enemy. When Assassins find themselves standing high atop the world on steeples, towers, or cliffs, there’s no faster way to reach the bottom than the Leap of Faith.

This unique gameplay mechanic is exactly what it sounds like: a high dive that can start a dozen feet or hundreds of feet in the air, and lands the player safely in a pile of hay or leaves or foliage. It stretches believability the higher in the air you make your leap from, but it’s a fun, useful ability that the games wouldn’t be the same without.

The First Civilization

At the heart of the conflict between the Assassins and the Templars is an ancient civilization of beings native to Earth, but older and more powerful than humans. This First Civilization, or the “Isu,” as they called themselves, are in fact responsible for creating humanity, in the games’ mythology.

The story goes that the Isu lived for millennia, becoming an advanced civilization like nothing the modern world has ever known. At some point, they genetically engineered a new race based on their own anatomy but physically weaker and shorter-lived, that they called humans and used as slaves. Two of these humans — who just happened to be named Adam and Eve — escaped Isu slavery and started a rebellion that grew into a full-blown war between the two species.

At the same time all of this was happening, a cosmic cataclysm was building: a solar flare big and powerful enough to destroy the Earth. While efforts were made by some of the Isu to save the planet, ultimately they were unable to stop the flare, and nearly all life on the planet was wiped out. Only a handful of Isu survived, while many more humans survived. Three Isu devised a way to help mankind long after they died out (more on them later), so ultimately it was the humans who grew and flourished.

Pieces of Eden

Today, Isu artifacts and technology, generally known as Pieces of Eden, are the most valuable and sought-after objects in the world, with both Templars and Assassins actively engaged in tracking down as many of them as they can. Abstergo Industries and its Animus technology exist primarily for the pursuit of these artifacts. Multiple times now, Abstergo has used the genetic memories of individuals whose ancestors came into contact with Pieces of Eden to locate those same artifacts in the here and now.

While there are various kinds of Pieces, the most prevalent are the spheres called Apples of Eden. These roughly golden orbs hold tremendous power. Holding an Apple, an individual can become a nearly unstoppable power, capable of directly controlling the mind and actions of others, and even killing them via pure will power. The Isu used Apples to enforce human slave labor, but interbreeding between humans and Isu resulted in hybrids capable of resisting the Apples. Among the first of these were the rebels known as Adam and Eve.

Other Pieces of Eden include Shrouds that can heal any injury and make its wearer nigh-invulnerable, Crystal Skulls that power telepathic communication, and a Sword of Eden that fires blasts of energy and instantly teleports the person holding it. Some Pieces are empowered or enhanced at special locations around the world, such as the Grand Temple and the Observatory. On occasion, some artifacts have even allowed humans to interact with the Isu who created them.

Juno

As the time of the Isu was nearing its end, three of their scientists separated themselves from the Human/Isu conflict and focused on solutions to the solar flare that would soon decimate Earth. They were Jupiter, Minerva, and Juno. As their experiments progressed, Jupiter and Minerva became aware that Juno had ulterior motives for her involvement and was trying to twist their solutions into scenarios that would allow her to take over the world.

They imprisoned Juno in their Grand Temple, an underground location where there was also stored a device called the Eye that could prevent the second cataclysmic solar flare. Over time, Juno devised a way to store her consciousness within the Eye so that she could survive her civilization’s downfall. Desmond Miles eventually found the Eye and activated it, sacrificing his life to save humanity — yet knowing that the cost would be to release Juno’s consciousness from her imprisonment.

Currently, Juno exists only in digital form, her consciousness roaming the data conduits of the Internet and massive server farms like those owned by Abstergo. She is currently attempting to restore her physical self before she makes herself known to the world at large, but it’s been a slow process.

In the most recent game in the series, Assassin’s Creed Syndicate, it was revealed that one Abstergo scientist is attempting to create/clone/grow a new Isu being entirely from scratch, using recovered Isu blood. Now who do we know that could make use of a brand new physical Isu body…?

Will the Assassin’s Creed movie reference Juno as the master manipulator behind pretty much everything that’s happened in this fictional universe? Or are Juno and the First Civilization simply too much for newcomers to swallow in a two-hour movie, on top of everything else the movie has to accomplish? We’ll find out on December 21, 2016.

Which elements of the game universe do you want to see in the movie adaptation? Do Fassbender and Ubisoft have the next big franchise on their hands? Sound off in the comments section.