It's been nearly 20 years since the first Underworld film premiered in theaters, and despite the host of negative reviews, it earned just shy of $100 million (against a budget of only $22 million), sparking a new wave of action-based fantasy horrors. Headlined by Kate Beckinsale, who played the vampire Selene, the first Underworld movie sparked three continuing sequels, a prequel, an animated short film, comic books, and more. For a time, there were even talks of a television spin-off and a number of crossover films between Underworld and other projects such as Marvel's Blade, the Resident Evil series, and the often-forgotten I, Frankenstein. Needless to say, there's a lot more to the Underworld universe than meets the eye, and the franchise's heavy cult following has kept it going for the better part of two decades.

But although Underworld has remained an admittedly small part of our cultural zeitgeist, it's an impressive franchise that has continued to reinvent the monster wheel. Part of what makes the Underworld movies both interesting and compelling, especially in an age where all sorts of dark fantasy stories are told, is that the franchise takes the time to ground itself in a reality not too unfamiliar, one that ties myth and legend into both science and the events of history. As a co-production between film companies across Europe and the United States, the first Underworld did the unthinkable in combining the high-octane action sequences of a film like The Matrix with a Shakespearian world filled with vampires and werewolves, called lycans in this reality (which is a much better name anyway).

Created by director/producer Len Wiseman, writer Danny McBride, and Kevin Grevioux, who also played the lycan Raze in the first film and its prequel, the Underworld series only got more intense with each new installment, building off the vast and rich history of this monster-infested world to tell a new and unique tale on every occasion. These flicks have been Romeo & Juliet-like love stories, revenge pictures, historical epics, mystical fantasies, gangster dramas, and even ventured into nigh-superhero territory the more sequels they released. If the Underworld series has proven anything after all these years, it's that it can still surprise you, and it does so while telling one of the most unique monster stories out there.

Historic Blood Feuds

Bill Nighy as Viktor with a glass of blood in Underworld: Rise of the Lycans
Image via Screen Gems

The ever-present conflict between the warring vampire and lycan clans is the heartbeat of the Underworld​​​​​​ story. The first film deals with Selene's struggle between her duty as a "Death Dealer" -- vampire assassins sent to dispatch lycan warriors -- and her love for Michael Corvin, a Scott Speedman-looking descendant of the original Alexander Corvinus (Derek Jacobi), the first of the Immortals and the father of the vampire and lycan clans. As Michael begins his lycan transformation, Selene is forced to make an impossible choice, and as she does so, she discovers the dark secrets behind her lineage and their reign of terror. The first two films, Underworld and its sequel Underworld Evolution, only scratch the surface of what these well-organized criminal syndicates are capable of as the monster-on-monster violence continues, building into even bigger battles with larger stakes.

While prequels in general have the potential to be underwhelming or even contradict the events of the originals, Underworld: Rise of the Lycans is arguably the best of the bunch as it goes above and beyond to shed light on the events of the first film. A truly standalone story, it exposes the class war between the imperialistic vampires, led by the ruthless Viktor (Bill Nighy), and their slaves, the always beaten down lycans who are eventually led out of slavery Exodus-style by Lucian (Michael Sheen), who just so happens to be the antagonist of the original 2003 film. Though the lycans are generally portrayed in a villainous light by the other four pictures, Rise of the Lycans reverses the roles by establishing the vampire's unrepentant dominance and exposing their bloodthirsty work in the 15th century.

While the Underworld series is not the first to establish dark histories between warring clans of monsters, its groundbreaking approach to portraying both sides as the heroes and the villains depending on one's perspective is something to be commended, especially for a series of films so often maligned. No other vampire versus werewolf story has given each side their own voice quite like Underworld has, but no wonder as the films establish that vampires and lycans come from the same source. In fact, these creatures aren't even deemed supernatural, rather their mutations are a result of a viral mutagen found in their ancestors, one who was bitten by a bat, the other bitten by a wolf. Vampires in particular rely heavily on scientific advancement to keep their race alive, while the lycans use more tribal means to spread their influence. Any fantastical additions are established later on, namely in the most recent installment, 2016's Underworld: Blood Wars.

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A Shadow War In The Real World

A beaten up Michael Sheen as Lucian with a vial of blood in Underworld
Image via Screen Gems

For the most part, the Underworld series takes place in our modern-day Europe, particularly in a version of our world that doesn't know anything about monsters, at least at first. In the years between Underworld: Evolution and Underworld: Awakening, humanity not only learns about the existence of vampires and lycans but does its best to hunt them down. The vampires, who had always retained political power of some sort, were no longer able to conceal their true nature from humanity. Likewise, the lycans became even more beastly than before, living off fewer scraps than they were used to and becoming bolder in the hunt. As the story continues, each side's tactics take interesting turns.

Although Awakening is the only Underworld film that takes the time to acknowledge humanity's involvement in this shadow war given that Blood Wars returns Underworld back to formula, the inclusion of characters like Detective Sebastian (Michael Ealy) and even Michael Corvin in the first film, remind us that although this battle has been fought for centuries, humanity is still fragile by comparison. The human experimentation on vampires and lycans is also particularly fascinating and elements of those procedures follow Selene and company into Blood Wars also. Needless to say, the almost gang-like factions of the vampire/lycan conflict are reminiscent of gangster pictures like The Godfather, especially since the first film includes a mobster hit on a pack of vamps. After all, this franchise isn't titled Underworld for nothing!

The war between the Death Dealers and the vicious lycans (brought to life by insanely detailed prosthetics in the first few installments before being replaced by some mediocre CGI) is unlike any other fantasy action you're used to. Not only do vampires use silver bullets and lycans use UV-infused ammunition of their own, but the characters often disregard their own weapons in favor of incredibly bloody fang-on-fang violence that just gets more intense with every new film. The secular limitations that the Underworld series puts on its characters and the world only serve to heighten the stakes, making these immortals far less mysterious and unkillable than previous adaptations all while also revealing their efforts to enslave one another (and humanity by extension) even more diabolical.

Selene, The Lycan Slayer

An armed vampire assassin takes shelter behind a pillar while a train passes behind her.
Image via Screen Gems

Coming off the heels of Buffy the Vampire Slayer and Alice from Resident Evil, Underworld introduced us to Selene, and it didn't take long for us to fall in love. Beckinsale's leather-clad Death Dealer doesn't much care about the world around her, only the few who catch her eye in it, which is naturally a part of her charm. Of course, that changes with Michael, and later their daughter Eve (India Eisley), but for the most part, this vampire assassin is out for herself. Though Beckinsale can play the fantasy action hero well (she also starred opposite Hugh Jackman in the action-fantasy Van Helsing), it's the personal touches that make Selene feel more, well, human. Though it would be easy to forgo any long-term character development in favor of her "badass" personality, each Underworld movie gives Selene something more to fight for, even if she also gains more to lose in the process.

Despite her anti-hero tendencies, Selene often finds herself in the middle of world-ending conflicts which only she can put a stop to. Without her, immortals may have taken over the world, and humanity wouldn't have so much as a snowball's chance. Often compared to a gritty '90s superhero, Selene (whose namesake comes from the Marvel Comics character Selene Gallio, an enemy of the X-Men) continues to engage in this eternal war between monsters, and every time she does her powers are put to the test. Yet, like some of our favorite heroes, she always overcomes, even death itself. Between Underworld: Evolution and the to-date final installment Underworld: Blood Wars, Selene has managed to upgrade her powers on multiple occasions, be it through the blood of Alexander Corvinus, genetic experimentation, or mystical Nordic means. No doubt, Selene continues to meet each new challenge head-on and, although there hasn't been news on a new film in a while, she shows no signs of slowing down.

While it's unclear if there will ever be another Underworld again (though we absolutely hope there will be), Kate Beckinsale seems up for it. Although a sixth film was at one point announced, with Beckinsale returning, she later backtracked on wanting to return at all, telling Variety that she'd "done plenty of those." Yet, as recently as 2021, Beckinsale went on record to state that she'd be willing again to return again to play Selene. Hopefully, this means that we'll get at least one more story following the Death Dealer that will round out the franchise, answer all our lingering questions, and give Selene the proper ending she deserves. She's certainly fought hard enough for it.