The world of Capcom's survival horror series, Resident Evil, has been a hit with fans since its initial release 25 years ago. The franchise has spawned a stream of surprisingly entertaining live-action movies, comics, animated films and merchandise. Many of the classic games have since been remade for new and existing fans, but a lot of the questions they present still remain a mystery for most gamers.

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Enter S.D. Perry, author of the Resident Evil novels beginning in 1998 and ending in 2004. Perry's books consist of five game novelisations (Resident Evil, Resident Evil 2, Resident Evil 3, Resident Evil: Code Veronica and Resident Evil 0) and two original stories. In many ways, the books shine an essential light on certain aspects of the overarching narrative, big and small.

10 Resident Evil 2: Why Do They Call Him 'Mr. X'?

Mr X looking in at Claire as she hides in a room

This one has many a fan scratching their head since the release of Resident Evil 2 back in 1998. After all, the official name of the gray-faced, trench coat wearing brute is T-00. He is one of the six tyrants in the T-103 series, instructed to retrieve the G-Virus sample enclosed in the pendant of Sherry Birkin.

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What fans of the books will tell you is that 'Mr. X' is in fact a term coined by Claire Redfield herself in the Resident Evil 2 novelisation, City of The Dead. Unsure of what the creature is when first encountered in chapter thirteen, Claire refers to it as "Terminator, Frankenstein's monster, Dr. Evil, Mr. X."

9 Resident Evil - Code: Veronica: The Guy Claire Can't Save

Claire Redfield in Resident Evil Code Veronica

During her exploration of the terrifying Rockfort Island facility, Claire Redfield finds herself in the lab where she discovers the bow gun and a little something else. After reading the memo about the pass number and attempting to leave the room, the alarm sounds and a cutscene ensues. During the scene, an Umbrella employee is seen banging on the window of the lab in desperation.

Claire tries to communicate that she can't open the door, at which point his face is slammed into the glass by a Bandersnatch. Book fans will recognise this unfortunate soul as Doctor Mario Tica from chapter three of the novel. Tica had been supplying private reports to Umbrella on his progress with the Albanoid project behind Alfred Ashford's back.

8 Resident Evil 2: Racoon City Police Station: Books And Bells?

Resident Evil 2 RPD

Plagued and tormented by the undead, it's understandable that many fans of the Resident Evil 2 video game never even questioned the fact that the police station has its very own clock tower and library. In fact, with the introduction of the 2019 remake, many fans still didn't bat an eyelid.

Readers, however, will understand. In the novelisation of the first game, The Umbrella Conspiracy, Chris Redfield remembers that the building used to be the Raccoon City Hall, thus explaining the clock tower. A growth in the town's population then saw it transformed into a library, before being converted into a police station four years later.

7 Resident Evil 2: When Leon Met Claire: Emmy's

Emmy's Café Resident Evil 2

Who can forget the iconic scene from the original Resident Evil 2 game, in which Claire bursts out of the fire escape before coming face to face with the barrel of Leon S. Kennedy's gun? But did you notice the name of the cafe? Emmy's is situated in the North of Racoon City, but what does this place have to do with anything?

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Well, fans of Perry's first book will recognise this as the same place that Chris' best friend, Bill Rabbitson, asked him to meet him at urgently, after he'd discovered something working undercover at Umbrella. Chris set out to meet his friend, unfortunately, Bill never showed.

6 Resident Evil: Brad Vickers' History Of Fear

Brad Vickers in Resident Evil 3 Nemesis

Fans of the first game are outraged at S.T.A.R.S. member Brad Vickers for taking off in the helicopter, leaving his fellow teammates behind with no place to run but the horrifying Spencer mansion. Ever wondered why Chris and co. managed to keep their cool?

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Turns out Brad had a habit of cracking under pressure. According to Perry's novel, "Vickers had a reputation for choking under the gun," so it was to be expected that in a fight or flight situation he'd, well, fly.

5 Resident Evil: Why Is Jill The 'Master Of Unlocking?'

Barry Burton Jill Gives Valentine a Lockpick in Resident Evil Remastered

"Jill, here's a lock pick. It might be handy if you, the master of unlocking, take it with you." Who can forget the clunky dialogue of Barry Burton from the original Resident Evil game? That line alone has been the burned into the brains of gamers for years.

So, what is so special about Jill Valentine that makes her a master of the lock and key? Well, according to the books, Jill grew up with her father, Dick Valentine, a master thief. She followed in his footsteps for a while before getting her life on the straight and narrow after her father was incarcerated, using her skills to join S.T.A.R.S.

4 Resident Evil - Code: Veronica: Just Shoot Him!

Claire Redfield in Resident Evil Code Veronica

After an epic escape from the guards in the Paris facility, including an amazing ability to dodge heavy helicopter fire, Claire finds herself surrounded by Umbrella soldiers. Feigning defeat before dropping to the ground and grabbing her gun with catlike reflexes (a move duplicated by Milla Jovovich in Resident Evil: Apocalypse), it appears she has escaped with her life.

Until she finds herself in a face-off with Rodrigo Juan Raval, that is. So, why doesn't Claire just shoot first and escape? Raval explains in the book that she may well have done if it wasn't for the fact her gun was empty. In fact, he even jokes that he'd have reloaded it for her if he knew of the horrors to come.

3 Resident Evil: Rebecca Chambers Plays Piano In Private

Chris Redfield Asking Rebecca Chambers About Piano in Resident Evil Remastered

Gamers may have been left wondering why on Earth Chris would think it wise to leave Rebecca Chambers alone, in a room in a zombie-infested mansion, to practice piano of all things. Readers, however, are privy to the knowledge that he's actually doing the right thing.

In chapter ten of the novel, Chris suggests Rebecca stays in the room for her own safety whilst he explores the mansion. She agrees, explaining that she doesn't have a gun. Out of pure boredom, Rebecca takes to the piano and starts reliving the lessons she had taken as a child. She hopes that perhaps her missing teammates will hear the awful noise and come running.

2 Resident Evil: Zero: The Guy On The Train

Bill Nyberg in Resident Evil Zero

The leech attack on the Orient Express has to be one of the most shocking intros to the classic games. What fans of the book Zero Hour will notice, however, is the gentleman that first spots the leeches sticking to the train window.

The smartly dressed man in spectacles seen going through his documents (note the Umbrella pin on his jacket) is, in fact, Bill Nyberg. Infamous pharmaceutical company the Umbrella Corporation employed him to help make various lawsuits "go away" with the help of their abundance of money.

1 Resident Evil 3: Nemesis: A Change Of Costume

Jill Valentine in Resident Evil 3 Nemesis

Despite the Resident Evil 3 remake seeing Jill in a more combat-appropriate getup, players of the original game will remember the skirt, blue tank top and boots (as worn by Sienna Guillory in Resident Evil: Apocalypse). This impractical outfit choice left many a gamer confused.

The outfit, after all, seemed a little too casual for a member of the legendary S.T.A.R.S. alpha team, fighting her way through a city of undead. As chapter three of the novel Nemesis explains, Jill made plans to escape the city from the south, cutting across farmland to route 71. She had made the decision to dress "for ease rather than protection from the elements."

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