One night, on his way to work, Michael is caught in the middle of a shootout between vampire Death Dealers and Lycans. Unknowingly, he was targeted by the Lycans for an genetic experiment, as his blood might have held a rare trait needed by the group. The goal was to gather a blood sample to test, though, due to interference from the Death Dealers, Michael escaped for a short period. Afterward, he had been ambushed by several Lycans at his apartment, however, was then rescued by Selene; a Death Dealer to whom he becomes completely devoted. And despite her efforts, he was bitten by the Lycan leader Lucian.
Lucian finally gained a blood sample, as the previous attack on Michael had been unsuccessful. Lucian's bite transmitted the Lycan virus, thus infecting Michael and setting him on the path to become a Lycan. Lucian's bite was also a sure way to keep Michael on their side and to discourage the vampires from running tests on him.
Having tested the blood sample taken by Lucian, they were able to establish that Michael was indeed the carrier of the rare immortal gene passed down by Alexander Corvinus. Discovering this, the Lycans made it their main objective to capture Michael. This was proven to be more difficult than they planned. During an attempt to escape, Selene was severely wounded and passed out at the driver's wheel due to a significant loss of blood.
The car plunged off a dock and into a river. When they finally got out of the sinking car, Michael bandaged her wounds and performed CPR. After resting for a part of the night, Selene regained consciousness. Going against the rules of Selene's coven, Michael was kept hidden in the coven's manor house for protection. Upon waking, Michael found himself confronted by Erika, another vampire from Selene's coven, snarling at him - Erika had discovered that Michael was bitten by a Lycan.
Startled, Michael quickly escaped from the manor and headed back to the hospital he interned at to treat his wounds. When at the hospital, he shared his ordeal with Dr. Adam Lockwood, who proved to be untrustworthy, relaying Micheal's tale to two men who seemed to be police. Upon seeing the two "officers", he fled the hospital, running back to the vampires' manor to find Selene. She drove him to one of the secret Lycan interrogation buildings and explained to him the full implications of his situation.
The pair were quickly discovered and, while Selene became engaged in battle, the two Lycan agents who had posed as police officers at the hospital managed to subdue and kidnap Michael. But, on the way, he began to change into Lycan form due to exposure to the full moon. The Lycans quickly injected him with an enzyme to stop the transformation. Michael was taken to Lucian where he met the Lycan leader for the second time and was finally made to understand the war from Lucian's point of view. When Lucian had bitten him, Lucian's memories had been passed on to Michael, causing Michael to see what had motivated Lucian in the war.
Soon, Death Dealers invaded the lair. In the commotion, Michael was shot with a lethal amount of silver nitrate bullets by Selene's jealous suitor, Kraven. Due to his Lycan physiology, the silver nitrate would have killed him, but on the advice of Lucian, Selene bit Michael. She had transmitted the vampire virus to his bloodstream, and thus Michael became the first Hybrid. Viktor, who condemned his daughter to death just to prevent such an occurrence, fought Michael. Michael initially gained the upper hand, as the Elder was thoroughly unprepared for his physical strength.
But despite being more powerful, Michael did not have Viktor's centuries of combat experience, and the vampire soon turned the tables on him. Viktor almost killed him, but was stopped when Selene interfered. She took Viktor's sword, slicing his head in half and thus killing him.
After Viktor's assassination, Selene and Michael went on the run from both Lycan and Vampire alike. Michael learned to transform at will and soon began to understand the power he had been given, yet refused to submit to the immortal need to drink blood for sustenance. His unwillingness to drink blood caused him to poison himself by attempting to eat mortal food. It didn't work and he vomited the food. Meanwhile, he was featured on TV as a missing person. Two policemen seeing this opened fire at Michael. He was severely injured, but was saved by Selene's blood.
After that, the duo confronted the last Vampire Elder, Marcus Corvinus, narrowly managing to escape him just as the sun rises the two hide in a warehouse where Michael grabs a med-kit to treat Selene's burns, but she shows him there was no need,both then confess their true feelings towards each other and spend the day making love.
After their escape, Selene and Michael met with Andreas Tanis, the Official Historian of the Covens, during which Michael put fear into the cowardly vampire. Later, they then traveled to the Sancta Helena, a cargo ship where Michael met his distant ancestor, Alexander Corvinus. Marcus' sudden intrusion and the subsequent battle caused Michael to be impaled and apparently killed on a steel beam beneath a nearby dock.
Selene went on to battle both William and Marcus alone; however, Michael's healing powers, much stronger than those of either Vampire or Lycan, allowed him to fully recover from his injuries. Michael descended to save Selene and engaged in a battle with William. William, though still extremely powerful, was weakened from eight centuries without feeding and Michael overpowered the immortal and emerged the victor, literally tearing William's head apart with his bare hands.
During this time, Selene also stabbed Marcus in the head with his own talon, and pushed him into spinning helicopter blades, killing him. After the defeat of William and Marcus, the sun began to rise in the distance, and both Selene and Michael notice that the sun no longer has an effect on Selene. They kiss as Selene reflects on the limitless possibilities that may come from the future.
Hybrid Powers and Abilities
Michael, as a Hybrid fusion of Vampire and Lycan at a cellular level, is far more powerful than either species, with none of their weaknesses; except for the craving of blood. His physical appearance consists of grayish blue skin, talons, black eyes, little fur, which accent most Lycan and Vampire features. Even though part Lycan, he shows little increased mass, with a Lycan's posture, facial construction, and their signature roar, while remaining seemingly humanoid.
It has been stated that the bloods to successfully produce a hybrid, they have to be from a pure source, such as a direct descendant in the Corvinus line, and infused with the other strains. The Corvinus Strain has the only known gene permitted to combine the bloodlines of both Vampires and Lycans, which would normally destroy one another due to incompatibilities.
In terms of sheer strength, Michael, even newly-turned, is by far superior to the either species; immediately after being turned, he demonstrated enough raw power to go up against the vampire Elder Viktor, with only Viktor's superior knowledge of combat allowing him to nearly win. By the end of Underworld Evolution, we can assume that Michael is still Selene's superior in terms of strength, being able to lift/carry at least 5 to 7 tons.
Michael went on to easily dominate the various Lycans he encountered in physical combat, even killing the original werewolf, William Corvinus, despite having only recently recovered from a near-fatal wound. Michael similarly possesses nearly unparalleled regeneration and speed, being able to move faster than the eye can follow and the ability to recuperate even from death.