21 years ago, a game launched that spawned a new genre of video-games — Resident Evil.

If you were there for the early days of survival horror, the T-Virus, and those lovely static backgrounds, you may find yourself needing to brush up on your Resident Evil lore. If you're new to the series and have never even set foot in the Arklay Mountains, this article will help you get up to speed for Resident Evil 7: Biohazard.

You don't need prior knowledge about the Resident Evil history before playing Resident Evil 7, though, but if you're interested, sink your teeth into this!

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Spoilers ahead!

Resident Evil

Resident Evil, or Biohazard as it is known in Japan, was first originally developed for Playstation in 1996 and has since become a popular horror franchise name, synonymous with zombies, Jill sandwiches and dodgy voice acting.

The elite S.T.A.R.S (Special Tactics and Rescue Service) team of the Raccoon City Police Department are investigating some strange cannibalized corpses on the outskirts of the city. On its way, the Bravo S.T.A.R.S team go missing. The Alpha squad, Jill and Chris' team, are sent to locate them. While searching, they find the crashed helicopter but are set upon by mutated dogs, causing them to flee into a supposedly abandoned mansion.

Mysteriously dead team members litter an impossibly locked up house, stuffed with monsters, zombies, and scientific documentation making it oh so painfully clear that this house is actually some kind of virus testing facility. But it's all gone terribly wrong.

After you've battled your way through the house, and have fought giant spiders and snakes, some bees and a giant mutated plant (as well as all the zombies) you find your way to the secret underground labs. Here we learn S.T.A.R.S member Albert Wesker is a traitor, and that everything that has happened in the mansion was to collect research for weaponizing the pathogen mutating all flora and fauna in the area. Wesker has been helping the Umbrella Corporation to lead the S.T.A.R.S. teams here to test and strengthen the creatures in the mansion, engineered to be bio-organic weapons. All along, you've been helping discover their weaknesses, so they can be genetically removed in future versions.

Wesker releases the Tyrant to put an end to the remaining S.T.A.R.S members. Tyrant is a giant mutated monster created from prolonged exposure to the virus, but Wesker ultimately fails to control it and dies as a result. The self-destruct for the facility gets activated and the team retreat to the launch pad. As they get there, the Tyrant appears one last time, you blow it up with a rocket launcher, and everyone breathes a sigh of relief as they ride off into the sunset in a helicopter as the facility explodes. Surely Umbrella wouldn't make the same mistakes twice, right?

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Resident Evil 0

Resident Evil 0 serves as a prequel to the events of Resident Evil 1, but it also runs slightly concurrently to the original game.

A sinister figure watches from a hilltop as leeches overtake a train. Shortly after, a helicopter containing the S.T.A.R.S. Bravo team crashes in the Arklay mountains on their way to investigate the cannibalistic murders that set the scene of Resident Evil 1. Taking control of Rebecca Chambers, a member of the S.T.A.R.S. Bravo team, she discovers the train that was attacked by mutant leeches and finds it infested with zombies.

She teams up with escaped convict, Billy Coen, and they both survive their ordeal using a unique inventory management system, that isn't at all annoying in the least. They're accosted by the sinister figure from the game's opening and are taken to a secret facility under the directions of Albert Wesker and Umbrella scientist William Birkin. Rebecca and Billy crash the train on its way to its facility destination, smashing it into a seemingly abandoned house.

During their investigation of the property, Billy and Rebecca learn the house was a training facility for the Umbrella Company where they had developed the Progenitor virus and saw its potential as a biological weapon. After Billy and Rebecca get separated, she runs into S.TA.R.S. Captain Enrico who tells her the other Bravo members will meet her at the abandoned house. A Tyrant creature attacks Rebecca, but she enlists the help of Billy Coen and ultimately survives.

The pair confronts the sinister leech man, and they learn he is the creator of the Progenitor's virus' last experiment — the Queen Leech. The leech enters the Progenitor creator's body, taking on his memories while manipulating his body to shapeshift. Taking a lift to the surface, they trigger the facility's self-destruct mechanism while the Queen Leech gives chase. After exposing the Queen to sunlight, they defeat her. Rebecca promises to keep Billy's involvement a secret, and she heads off to the Resident Evil 1 mansion to meet the Alpha team.

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Resident Evil 2

Two months after the mansion events, the unthinkable has happened, and the entire of Raccoon City is almost now completely infested with zombies. This time, Leon Kennedy — rookie cop, and Claire Redfield — looking for her brother Chris, are embroiled in the horror.

Broadening their horizons with the success of Resident Evil, Resident Evil 2 moves from the relative seclusion and so-called comfort of the mansion to the vast city. Raccoon City Police Department is left mostly abandoned. Everyone inside is dead. Claire discovers that Chris has gone to investigate Umbrella in Europe, and Leon finds that there are simply no living beings left to serve as a police officer. They decide to leave the city while scanning for survivors on the way after becoming separated.

Claire meets Sherry, a little girl being pursued by her monstrous, self-infected father, the scientist William Birkin. Leon, on the other hand, meets Ada Wong, who has been spying on Umbrella for a rival pharmaceutical corporation.

Claire learns that Racoon City's police chief has been hiding evidence of the attacks on the outskirts of town, after receiving bribes from Umbrella. He had also been suppressing knowledge of the new virus, the G-virus, capable of mutating humans and turning them into large biological weapons.

While plotting their escape through Racoon City's sewers, Leon and Ada discover Sherry, who promptly flees assuming the pair are zombies. Sherry leaves her necklace behind, and as the pair retrieve it, a mysterious woman opens fire. Leon takes a bullet for Ada after a woman shoots at her. The woman is Sherry's mother, Annette, and wife of the G-virus creator, William Birkin. After a brief struggle over Sherry's necklace, Ada causes Annette to plunge over a deep sluice in the sewers, supposedly to her death.

It is later discovered that the necklace contains a sample of the G-virus. William implanted Sherry (his own daughter) with an embryo to produce mutated offspring (...his own daughter). Leon and Claire take Ada and Sherry with them to Umbrella's secret underground facility.

During a descent into the facility, Ada is attacked by the heavily mutated William Birkin. Leon manages to defeat the monstrosity, taking Ada to a first aid facility in the entrance hall. Leon leaves to find something to heal Ada, but along the way, he encounters Annette who is clearly going insane. As she is about to shoot and kill Leon, a Tyrant appears, causing Annette to retreat. Ada comes to Leon's rescue but ends up crushed in the process. She professes her love to Leon before she dies.

Annette tries to escape with another sample of the G-virus but is stopped and nearly killed by William, who just doesn't want to die. Before shuffling off this mortal coil, she gives Claire the recipe for an antidote to the embryo mutation within Sherry. Claire and Leon meet at an emergency escape train. William appears one last time, however, this is short lived when he is destroyed by the facility's self-destruct sequence.

Resident Evil 3

We're with Jill Valentine from Resident Evil 1. Set the day before the events in RE2; she is also trying to escape Racoon City. As we know from RE2, almost the entire city is now zombified by the T-virus. Jill is confronted by a new enemy, Nemesis, a special monster created by Umbrella for the sole purpose of hunting down members of the S.T.A.R.S. team. Naturally, S.T.A.R.S. members were the only witnesses to their criminal experiments from the first game.

Jill also intercepts three members of the Umbrella Biohazard Countermeasure Service, Carlos, Mikhail, and Nicholai, the latter who informs her a rescue helicopter will come if the bell of the clock tower is rung.

On the way across town Nemesis traps the team in a cable car, and Mikhail sacrifices himself with a grenade, causing the car to crash into the courtyard below. Jill rings the clock tower bell, but Nemesis appears and destroys the helicopter, infecting her with the T-virus in the process. Carlos rescues Jill and brings her inside the clock tower, taking over for a while to find her a cure.

Carlos finds an experimental cure inside the Racoon City General Hospital (where else?!), and he finally returns to save her life. Jill heads to Raccoon Park. Entering the caretaker's cabin, she finds Nicholai, whom we discover is a shady character, indeed. He is under special orders by Umbrella to gather tactical and combat data on the zombies and other B.O.Ws, under the guise of being sent into the city to help.

An enormous mutated grave worm attacks Jill, and upon defeating it she makes her way into an abandoned factory bordering the park. Carlos meets Jill inside and informs her that the government has approved the plan to send a nuclear strike to wipe out the T-virus threat in Raccoon City. If she doesn't want to be a Jill scorch mark, she needs to get out of the city.

Before escaping, Nemesis appears one last time more mutated than ever. Jill blasts him with a prototype rail gun, escaping to the yard. She is rescued via helicopter by Barry Burton from RE1. Raccoon City is nuked off of the face of the earth to prevent the T-virus spreading any further.

Resident Evil: Code Veronica

Claire Redfield is still looking for her brother Chris while infiltrating an Umbrella facility in Paris. She is captured and imprisoned on Rockfort Island, somewhere in the Southern Hemisphere. She is freed by Rodrigo Juan Raval, Umbrella security guard after an outbreak of T-Virus on the island.

After teaming up with another inmate, Steve Burnside and attempt to escape the stricken island, they're confronted by facility commander Alfred Ashford. Alfred is a multiple personality, housing his own, and his twin sister Alexia. Albert Wesker is also on the island, causing zombie outbreaks and taking names, looking for his own sample of the T-Virus developed by Alexia.

Steve and Claire are attacked by Steve's zombified scientific researcher/whistleblower-for-cash father. His father was caught trying to sell research information, and he and Steve were both imprisoned, while Steve's mother was killed. During their escape via plane, Alfred switches to Alexia and flies to an Antarctic Umbrella research facility. Alexia, the real Alexia, is in a cryogenic sleep to counteract the injection of the T-Veronica virus she had taken. Alfred is almost killed by Claire and Steve, falling into a ravine and awakening a T-Veronica monster, 'Nosferatu'. After defeating it, the pair attempt to escape the facility, but are interrupted by Alfred witnessing Alexia's return to life, where she promptly sprouts tentacles and captures them, before Alfred snuffs it.

Chris arrives at Rockfort Island, but learns from Raval that Claire has already moved on. Chris encounters Wesker, who he notes has become considerably stronger and faster than any normal human being. Alexia interrupts the Chris-pummelling and Wesker, surprised by her apparent state of wakefulness decides to go to her in Antartica. Chris, not being one to be left out also heads there and reunites with Claire, finally! They set off to find Steve.

Steve has been experimented on by Alexia, turning him into into a reptilian monster. She is chased into a prison cell when he attacks, but as Alexia's own tentacles attempt to kill Claire, she is protected by Repto-Steve. Taking a tentacle to his reptile chest, the tentacle leaves, Steve reurns to his human form, confesses his love for Claire and dies. Aw.

Wesker realises that Alexia has gotten way too strong (and can produce fire at will), and leaves the manly-man fighting up to Chris. Chris momentarily defeats her, setting off the facility's self-destruct mechanism, which unlocks all the doors - freeing Claire. Alexia becomes even more mutated, taking an insectoid form. Chris blasts her with a plasma weapon, and on the way to the emergency elevator, Wesker is glimpsed as Steve's body is retreived for further testing, as he is now the only T-Veronica host.

Claire and Chris attempt to escape the island, only to be temporarily thwarted by Wesker, who releases Claire to wait in the plane for her brother. Before he can finish Chris off with his super-mutant strength, an explosion separates them. Wesker vows the next time they meet he will have his revenge, and Chris vows to bring down Umbrella. The facility blows up.

Resident Evil 4

Set 6 years after the events in Raccoon City, Leon Kennedy has moved on from zombie-infested street policing, and is now working for the Secret Service. He's on an assignment to locate and rescue the U.S. President's kidnapped daughter, Ashley Graham.

Leon is sent to a rural part of Spain, where Leon suspects a cult are holding Ashley. The Los Illuminados, "The Enlightened Ones" reign here, and they're the strange sect who have kidnapped the President's daughter.

Leon is implanted with Las Plagas when he is captured by the village chief. Las Plagas is a mind-controlling parasite. He and his fellow captive, Luis, a Las Plagas researcher manage to escape but quickly split up.

He learns that the plan of Los Illuminados is to infect Ashley with Las Plagas and send her back home to America where she will be able to infect the President. Then Los Illuminados' leader, Saddler will be able to control the President's mind and begin enacting his plan for world domination through him.

Leon kills the village chief, and he and Ashley both escape. They attempt to seek refuge inside a huge castle, which happens to be home to one of Saddler's henchmen, Ramon Salazar. Salazar's castle is booby-trapped and full of cultist minions, causing Leon and Ashley to become once again separated.

In the meantime, Leon's Las Plagas researcher friend, Luis has been looking for pills to slow the infection rate for the implanted parasites, and also a sample specimen. He manages to meet with Leon with both of these things but is killed by Saddler in the hand-off. Saddler takes the Las Plagas specimen, but Leon manages to keep the pills.

Leon runs into Ada, who apparently survived the events of RE2, but their meeting is short lived. He continues to fight through the castle and kills Salazar. He then heads to a nearby research lab where he discovers an old friend of ours from the past wasn't as dead as we expected. Jack Krauser is Ashley's kidnapper, and Leon learns that Jack and Ada are both working with none other than Albert Wesker (RE1 traitor). They are both attempting to procure a sample of Las Plagas for Wesker, who has his own plans. Saddler orders Krauser to kill Leon. Leon prevails, finds Ashley and proceeds to remove Las Plagas from both of their bodies.

Leon faces down with Saddler and defeats him with the help of Ada. But the island is about to self-destruct, and the only way to safety is a white knuckle ride on Ada's jetski.

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Resident Evil 5

Chris Redfield, now super-muscly, has left S.T.A.R.S. long behind, and is now working for the Bioterrorism Security Assessment Alliance (BSAA). He is sent deep into Africa, where he and his partner Sheva are tracking down a black market bio-organic weapon seller, Ricardo Irving. Lo and behold, they discover that the town has been infected with parasites, and the Alpha BSAA team has been killed.

Chris learns his old partner Jill is presumed dead following an altercation with the series' big evil Albert Wesker some time ago. Fake documents left by Wesker lead Chris and Sheva to a diversion which they think will take them to Irving, while a B.O.W. kills the rest of their team. Chris sets out to find out whether Jill is still alive or not.

Sheva's mentor is found after the B.O.W. attack, and they track Irving down who injects himself with Las Plagas and mutates. His last words lead them to the location of a plant that the T and G virus was derived from, and they learn a new virus has been made, the Uroboros.

The company funding the BSAA, Tricell, had bought an old Umbrella underground facility and continued their research. Test subjects are still inside, and Chris finds Jill's containment capsule, but she's not in it.

Wesker now has Dragon Ball Z-powers thanks to various mutagens and sends a parasite-infected Jill to attack Chris and Sheva. Pumping himself with Uroboros, Wesker also joins the fight, mutating himself in the process. He falls into a volcano, but even the lava isn't enough to finish him off. How many times has Wesker died at this point?

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Resident Evil 6

We've lost sight of the original Resident Evil trilogy now. This game is a cluster grenade of almost every conceivable character being brought back from the dead, or randomly appearing after years of silence.

The story is set ten years after the outbreak in Raccoon City, and the US President makes a shock announcement that he was in on it, before mutating live on air. Leon Kennedy and his new partner, Helena Harper chase the National Security Advisor, Derek Simmons, to China, who divulges he had assisted with the plan to assassinate the president. Simmons is also affiliated with "Neo-Umbrella," an off-shoot of the franchise's evil corporation. Wesker's son, Jake Muller, is on the run with Sherry Birkin from RE2 to get his blood tested for C-Virus antibodies (because of course, he has them). The C-Virus is an all-new super virus that combines various other pathogens from throughout the series. Resident Evil 6 is a tad convoluted.

Jake and Sherry end up captured in China but escape after six months, to find themselves conveniently in the same province as everyone else from the Resident Evil pantheon.

Ada Wong causes all kinds of trouble, revealing herself as the leader of Neo-Umbrella. She wipes out Chris Redfield's team, leaving him alive, but with trauma-induced memory loss. He regains his memories and returns to work, being sent to China where he once again confronts Ada. Sherry gives Leon Jake's medical information, just in case. Leon and Helena face Derek Simmons once more, who elaborates that he helped assassinate the President to prevent him from telling the truth about Raccoon City, which would have lead to a loss of global authority. Leon tells Chris about Jake's antibodies, capable of forging a C-virus vaccine. He asks Chris to rescue Jake and Sherry. The pair escape to an underground facility Neo-Umbrella facility, while Ada helps Leon and co. to kill the C-Virus mutated Simmons.

Sherry and Jake are rescued before a huge invasion sets in, and Chris' partner Piers injects himself with C-Virus to give them a battle advantage. Piers beats down the mutant enemy Heos, and saves Chris, before Heos rises again for one last attempt. Piers kills Heos, guaranteeing Chris' escape and blows up the entire Neo-Umbrella base.

As the game is told in various overlapping character perspectives, Ada's game gives some clarity to the otherwise confusing plot. Her scenario suggests that the Ada encountered by Chris and Piers before they lost their memory was only a doppelganger. The real Ada was in China helping Leon blow up the Neo-Umbrella base (she did tell him she loved him in RE2). Confused yet? You can probably skip this one.

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And that's a wrap!

There are tons of additional Resident Evil plot points out there, but this is to give you a general overview of the state of the Resident Evil world moving into 7.

Pharmacological technology is highly advanced, with sprays that can repair grievous tissue damage. Bioterrorism is a fact of daily life, with large outbreaks occurring all over the globe. But Resident Evil 7 strays from the global disasters of its predecessors.

Resident Evil is such a well-loved franchise, and the latest game looks as though it will bring the series back to its grizzly survival horror roots. We need only wait until January 24th to find out for sure.

Which is your favorite Resident Evil? Let us know in the comments.

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