The main protagonist of the series. Selene is a vampire and one of the best Death Dealers in the Fur Against Fang war, believing that her family were slaughtered by werewolves. She was turned by Viktor because she reminded him of his deceased daughter Sonja. She is a skilled marksman and fighter, making her probably the most prominent Badass in the series.She has a change of heart when she falls in love with human turned werewolf Michael Corvin, and is responsible for turning Michael into a Hybrid Monster. She finds out that Viktor killed her family, and she kills him by slicing his head in two. In Evolution, she learns her family built William's tomb, hence why Viktor killed them, and becomes a true immortal after drinking Alexander Corvinus' blood, and kills Marcus.
Badass Longcoat: Of the leather variety. In Awakening she makes a point to break into a store so she can get a new longcoat. This one isn't made of leather, so she ditches it when she comes across a leather one.
Cassandra Truth: Her attempts to warn Viktor about Lucian possibly being alive.
Cute Little Fangs: First seen when she bites Michael to make him a vampire. Awakening shows the first time she uses them to drain a person, who had just shot her in the head. It heals the wound, and rejuvenates her.
Immortal Heroine: As a vampire she can be killed, until she drinks Alexander Corvinus' blood and becomes a proper immortal.
Invinicble Heroine: The case can be made for this, as she almost never takes any real damage when compared to other characters, up to and including Michael who is supposed to be the ultimate fusion of the two species and was briefly killed before resurrecting, and Alexander Corvinus, from whom she gets upgraded to the point that Michael's hybrid state may as well have been a child's toy compared to Selene's power being equivalent to creating Superman in a lab. She's virtually unstoppable to begin with just in the first film. It just snowballs on from there as she's pretty much a God by the time of the fourth film.
Of Corsets Sexy: Selene wears a corset over her catsuit. The sequel implies that the corset has an actual function: being bullet-resistant, which comes in handy when the character gets buckshot straight to the chest. The corset comes away with only minor damage, and Selene just gets pissed off.
Super Strength: She had vampire's strength in the first two films but when she drank Alexander Corvinus' blood and became an Corvinus strain immortal vampire, her strength went up higher then before. Notably, she shoulder-checks a van in the third film with enough force to flips it.
Superpower Lottery: Thanks to drinking Alexander Corvinus' blood, not only she has much more higher inherit vampire powers, but she can endure sunlight and by the third film, she can pour re-start hearts after cutting open her palm and then re-starting the heart.
A descendant of Alexander Corvinus, Michael is an ordinary nurse until he becomes the target for the Lycans to create the first vampire/lycan hybrid. He is turned into a werewolf by Lucian and later is bitten by Selene to heal him from gunshot wounds. He is turned into a hybrid, becoming one of the series' many badasses. He becomes Selene's boyfriend and currently one of two people to still be alive in the series, the other being Selene.
Badass: When allowed to be. Sadly, he doesn't get to show off his abilities much since the series is focused so much on Selene. He's supposed to be the strongest creature that could exist in the Underworld franchise, but that gets thrown out the window very quickly in favor of Selene.
Battle Couple: With Selene. Only really comes up once or twice in the entire franchise though.
Body Horror: Michael's transformation into a hybrid looks quite painful, especially since he seems to switch between werewolf and vampire several times before his body finally gets the balance right.
Demoted to Extra: He definitely is this in Awakening, seeing as he is practically non-existent in the film aside from one flashback and a single scene where he's shown encased in ice. But one can make the argument that this is also true in Evolution as well, as he's taken out of focus for the better part of the middle-to-latter half of the movie, when he finally pops up again to raise some hell. Though to be fair, he was technically dead for a good part of that.
Hospital Hottie: Is a medical intern in the first film, before he goes on the run with Selene.
Living MacGuffin: In the first movie. His status is revoked entirely by the second film and by the fourth, he's practically non-existent as a character.
The Lost Lenore: Implied in the theatrical cut, confirmed in the director's cut. His wife was killed in a car crash, he became a doctor afterward and moved to Prague (the supposed setting) for a fresh start.
LEGO Genetics / Magic Genetics: Michael is the only descendant of Alexander Corvinus who has the same blood type as his, allowing Lucian and Selene to turn him into a vampire/werewolf hybrid.
Put on a Bus: In Awakening, Michael is seemingly killed, but revealed to be frozen in Antigen's labs, only to escape and disappear.
Single Specimen Species: Technically the first hybrid ever in the millenium-plus existence of vampires and lycans (the unborn child of Lucian and Sonja would have been one), until Marcus also turns into a hybrid... then Marcus dies leaving Michael the only hybrid in existence. If you want to get technical, this also applied when Marcus was still alive, as Michael is a Lycan hybrid, while Marcus was a Vampire hybrid. Whichever way you look at it, Michael is the first and only of his kind.
He's not the only hybrid around anymore as of Awakening, but he is the only one of his type of hybrid.
Unskilled, but Strong: When he becomes a hybrid his unprecedented strength and healing abilities allow him to fight some of the most dangerous beings around. His lack of training bites him in the ass more than once though.
The first Lycan born with the ability to turn back into a human. Lucian falls in love with Sonja, a vampire, and they become Star-Crossed Lovers. When Viktor finds out, he has his daughter executed via sunlight, kicking off the war between vampires and Lycans. Lucian fakes his death with help from Kraven and spends the next few centuries trying to find a descendant of Alexander Corvinus who has the right blood to create the first Hybrid Monster. He succeeds in turning Michael into one with help from Selene, but is gunned down by Kraven.
Anti-Hero: Turns out to have been a Type III-IV in the first movie.
Anti-Villain: Type IV. By the end of the first movie, he is a villain only by virtue of being on the opposite side. Unless you're one of the hapless Corvinus descendants he's managed to track down and capture...
Well-Intentioned Extremist: Lucian has killed generations of Alexander's descendants to find one whose blood can mix both werewolf and vampire blood, in order to avenge his dead lover and unborn child.
Also, it must be stressed, to prevent the vampires from wiping out his species.
The Big Bad of the series. Viktor is one of the three Vampire Elders, and the foster father of Selene. Having Fantastic Racism against Lycans, Viktor went to great lengths to either control or kill them including killing his own daughter Sonja when she became impregnated with a vampire/Lycan hybrid.
Dual Wielding: After losing his sword he whips out a pair of hidden daggers from his sleeves. Subverted as he never gets to use them.
Fantastic Racism: Viktor despises the werewolves, and considers a hybrid to be an abomination.
Hidden in Plain Sight: Viktor hid the keys for William's tomb in plain sight, one being a necklace owned by Sonja, and the second hidden inside his own body.
Hoist by His Own Petard / Idiot Ball: Viktor's plans keep coming back to hit him in the face. He creates an army of Lycans; they rebel. He kills Sonja and her child; Lucian swears revenge and makes a new hybrid. He turns Selene into a vampire; she kills him. What a tangled web we weave.
I Did What I Had to Do / Well-Intentioned Extremist: Subverted. Viktor honestly thought he was doing what was best for the coven, but every last one of Viktor's actions (deceiving Markus, imprisoning William, killing Sonja, murdering Selene's family and turning Selene into a vampire, etc.) directly or indirectly leads to the vampires being all but wiped out by the fourth movie.
Idiot Ball: He pretty much ran with this one (see above), but punching Singe to death and not having his bleeding body immediately removed will forever be a classic.
I Hate You, Vampire Dad: Sonja and Selene both suffer this. Viktor is shown to be devastated by having to kill Sonja.
He wasn't all too happy about possibly having to kill Selene, either. His immediate reaction after hurling her halfway across a room, for instance...
Manipulative Bastard: Viktor managed to fool all the vampires into thinking that he is the first vampire in existance, imprisoned William for all time and went to extra lengths to ensure Marcus couldn't stop him - which failed spectacularly. Not to mention making Selene think her family was killed by Lycans for 600+ years.
Nice Job Fixing It, Villain: Two instances- killing Sonja was what started the war in the first place. Not believing Selene results in his worst fear being recognized in the form of a hybridized Michael Corvin and his death.
Super Strength: As an Elder Vampire, he's a fair bit stronger than regular vampires and werewolves, as shown when he does a Neck Lift on a transformed werewolf, which leads into a Neck Snap. He can even match the hybridized Michael Corvin, though Corvin is a lot faster.
Ungrateful Bastard: Marcus comes to Viktor while the latter is on his death bed and grants him immortality. How does Viktor repay him? By wresting control of the coven away from Markus, indefinitely imprisoning Markus's brother, and having the vampires' history rewritten so that Viktor, not Markus, is the first and most powerful of the vampires.
Lucian transforms into Lycan form to save Sonja from becoming werewolf kibble. Viktor's response to this is to have him publicly flogged to near-death for removing the slave collar that would have prevented said transformation. Mind you, he gave Sonja a brief lecture earlier about showing gratitude to Lucian for saving her life. When she calls him on it he responds that letting Lucian live is his gratitude...
...and then decides to have Lucian killed anyway as a cautionary tale to any would-be upstarts.
Selene potentially all but saved Viktor, and the coven, from certain doom by breaking the Chain and making him aware of her concerns. After literally centuries of her Undying Loyalty to him, Viktor refuses to hear any of it and orders her judged (which would almost certainly result in her death). After Selene acquires undeniable proof for her suspicions, Viktor refuses to absolve her unless she kills Michael, who's totally innocent and only the "enemy" by being turned against his will.
Not completely without justification in Michael's case; the hybrid issue aside, Viktor probably just wants to avert what happened the last time a descendant of Corvinus got infected with lycanthropy.
The second of the Vampire Elders. Hardly anything is known about her, making her a bit of a Flat Character. However, she aided Marcus and Viktor in catching William and sided with Viktor to imprison him forever.
The third Vampire Elder, and son of Alexander Corvinus. He was bitten by a bat and became the first vampire. With his Lycan brother William out of control, Marcus recruited Viktor, Amelia and their army to catch his brother, only for Viktor to double-cross him and take control of the vampires and imprisoned William forever. In the second film, he is turned into a hybrid and vows to free his brother and rule the world with a new series of hybrids.
Angsty Surviving Twin: Is this for a short time, as he gets killed not long after William's death, but that scream he does when William dies is proof enough.
Affably Evil: While he gets the idea to rule the world with hybrids, his main goal is to reunite with his beloved brother.
A God Am I: Intends to create a new race of immortals, with himself as their God.
Badass: He can bring down a helicopter just by pulling on a rope. However, it leads to his Karmic Death.
Bat out of Hell: He has large bat wings in his hybrid form. Whether or not he had these beforehand is unknown.
Blood Brothers: Marcus and William have a strong bond. They had a third brother who was only human and presumably died years ago.
Genetic Memory: He can see the memories of others by drinking their blood, something which Viktor could also do (and Selene as well, at least as of Awakening). Selene, Kraven and Andreas Tanis all become victims to his ability.
Where It All Began, Alexander Corvinus became the first true immortal after his village was ravaged by a plague which he was able to mold into what gave him his immortality. He then fathered three sons, Marcus, William and a third son. Marcus and William were bitten by a bat and a wolf, becoming the first vampire and werewolf, leading to the rest of the events in the films. The third son remained human, but carried the Corvinus Gene that would later lead to Lucian's quest to find a descendant who could adapt to vampire and Lycan blood.
Almighty Janitor: He's been cleaning up the chaos the vampires and Lycans have been causing for centuries.
The daughter of Viktor, and Lucian's lover. The two were the original Star-Crossed Lovers, Sonja becoming impregnated with the first hybrid. Viktor was distraught when he found out and regretfully had her executed via sunlight, kicking off the war. Lucian stole her necklace, actually one of the keys to William's tomb.
Faux Action Girl: Despite being leader of the Death Dealers, Sonja needs to be rescued a lot.
To be fair, she needs rescuing from overwhelming odds. She did kill three lycans while being chased in the beginning of the film, and she managed to one-up Viktor in their sword fight. And unlike Selene, she didn't have access to automatic firearms.
Viktor's Dragon, Kraven is in charge of the old coven during Viktor's slumber. A Smug Snake and a Manipulative Bastard, Kraven helped fake Lucian's death to become a hero among the vampires, and to keep Lucian's plan under wraps. Their ultimate agreement is to eliminate the vampire elders, so Kraven can rule the vampires and Lucian can create the hybrid. Kraven has a thing for Selene, despite being in a relationship with Erika.
Blatant Lies: Everything that comes out of his mouth is a lie.
Opportunistic Bastard: Kraven has no loyalty to anyone or anything but his own ambition. When spared from death by his own cowardice at the hands of the Lycan werewolves' leader Lucien, Kraven aligns himself with Lucien's plans to seize power for himself in the vampire covens. Kraven seizes on a chance to allow Lucien's Lycans to massacre the vampire elder Amelia, and when his treachery is exposed, he later betrays and murders Lucien before taking advantage of the resulting power vacuum from the large scale battle at the conclusion of the second film to attempt to murder the final sleeping vampire elder and rule the coven. Lacking his own plans, Kraven simply ingratiates himself to whoever is in power for his own success and has no compunction taking any chance fate gives him in pursuit of it.
Sissy Villain: Selene, Lucian, and damn near everybody thinks he's a little bitch. He even kills Lucian for call him out on it.
Lucian's closest friend and a Scary Black Man. He became a Lycan in Rise of the Lycans and helped Lucian fight back against their vampire suppressors. He has a rivalry with vampire Soren going back to their earliest days. And yes, his voice is actually that deep.
Selene's Black Best Friend, Kahn is the weapon's specialist in the coven and head of security. He clashes with Kraven, and is just as suspicious of him as Selene is. He is a skilled marksman and inventor, replicating the Lycans' sunlight weapon with silver bullets which can harm Lycans on the genetic level.
Kraven's one-and-off girlfriend, Erika is pretty much used by Kraven for sexual tension and he treats her like dirt whilst pining after Selene. Erika discovers Michael is a Lycan and tells both Selene and Kraven. Erika ditches Kraven and frees Selene from her imprisonment to get back to Kraven. Her fate afterwards is unknown. In the novelization, she and Selene have a somewhat tenuous friendship, and it's mentioned that she left the mansion and "wondered if Viktor liked blondes."
Friend Versus Lover: Selene, who is her friend and love interest for Kraven (although Selene doesn't want to be).
What Happened to the Mouse?: Erika never appears in Evolution aside from a flashback cameo, so it's assumed Marcus killed her when he destroyed the coven.
A scientist Lycan, Singe has spent years trying to find the right carrier of the Corvinus strand, and is at his wit's end. Lucian delivers him Michael's blood and he is proven a carrier. Singe is sent to help retrieve Michael from the vampires but is captured by Selene and forced to reveal Lucian's plan and Kraven's treachery. After Amelia is killed, Viktor punches him to death. His split blood leads to Marcus turning into a hybrid.
Introduced in Awakening, David is a survivor of the Purge. The Idealist of the film, David aids Selene, willingly helping her and Eve escape the humans and Lycans. He believes the vampires should honor their predecessors and fight back, being at odds with his father Thomas.
Back from the Dead: Killed by Lycans, but is resurrected by Selene when she cuts open her palm and then forcefully using her hand and immortal blood to restart his heart.
The Lancer: To Selene since Michael is unavailable. Shared with Detective Sebastian.
The first human since Michael to become a prominent character in the films. A police detective who pities the vampires and Lycans, Sebastian teams up with Selene to take down Antigen to save Eve and avenge his dead vampire wife.
Badass: Single-handily launches a one-man assault against Antigen, kills a guard with a rocket launcher, helps stop a van carrying off Eve, tries to fight the Big Bad, and survives with the intention to cover Selene.
Well-Intentioned Extremist: He comes off as one, wanting to protect humanity from Lycans and vampires. Turns out he's a lycan, and what he wants is to wipe out vampires and have Lycans become dominant.
A wolf known as the Uber Lycan, Quint kidnaps Eve so Dr. Jacob Lane can use her to create an army of Lycans, and is actually being Lane's son.