Selene is a character from Underworld and Underworld: Evolution. She is the main protagonist in both films and is portrayed by Kate Beckinsale and by Kate's daughter, Lily Mo Sheen, in Underworld: Evolution in flashback scenes as a child.
Selene was born to a Hungarian family. Her father was a well-known blacksmith who helped design a fortress for a general named Viktor. The fortress was actually a dungeon intended for the imprisonment of the Lycan Elder, William Corvinus, condemned for his bloody and destructive behavior and a definite persona non grata for Viktor. After Lycans presumably killed her family, Selene was the only one left alive who had walked through the corridors of the fortress. However, she did not know that her family was slain by Viktor himself, and believed Viktor had saved her from the Lycans. That night her family was killed and she was made into a vampyre by Viktor.
She became a Death Dealer, fighting against the Lycans for vengeance on the atrocities she believed they had committed against her family. She also exiled the official Historian, Andreas Tanis, on Viktor's orders. Many years later (shortly before the events portrayed in Underworld) she became an object of romantic interest for Kraven, the Coven's regent, however she did not reciprocate his advances.
She is proficient with many weapons, both medieval and modern. Modern firearms that she uses include the Walther P99 and a variety of automatic machine pistols. In both movies, she is seen jumping from a ledge at least 100 feet in the air and landing without injury.
Selene frequently demonstrates superhuman physical abilities. She uses super strength to pin Michael against a wall several feet off the ground, performs spectacular leaps, and strikes her enemies with tremendous force. She kills younger vampyres with just a few blows. She takes a shotgun blast to the abdomen without flinching and manhandles four police officers as if they were rag dolls. She also has the ability to hold her breath for long amounts of time, as humans needed scuba gear to make an underwater dive in Underworld: Evolution. While she did it with one breath, she gasped for air when she reached the surface. After fortifying herself with some of Alexander Corvinus' blood, she is able to lift people with one arm and go toe to toe with Markus, another Vampire Elder and actual first Vampire (not Viktor as he led all to believe), in his hybrid (vampyre dominant, half-bat) form. She has been slammed against stone walls, breaking the stones, but with no ill effects. She is also able to withstand direct sunlight, making her a true immortal. By the end of the second film in the series, she is completely devoted to Michael, and he to her, and together, as each has few if any weaknesses that are offset by strength in the other, they form a strong alliance against any who oppose them.