Overview
Selene is a character and the main protagonist of the Underworld film franchise, in which she is portrayed by Kate Beckinsale. The character is introduced in the first film, Underworld, as an elite vampire assassin known as a "Death Dealer" who hunts down the Lycans for allegedly murdering her family. She becomes attracted to a human named Michael Corvin and, upon discovering that her sire and adoptive father Viktor was actually responsible for the death of her family, defects from the vampire clan.
Creation
Selene was created by Kevin Grevioux, Len Wiseman, and Danny McBride. According to Grevioux, Selene is based on the X-Men villain of the same name appearing in comic books published by Marvel Comics. Selene was introduced in the first film of the series, Underworld.
Character
Selene was born in the late 14th century and grew up as a normal, happy, vibrant child. She and her sister Cecilia loved painting pictures and playing games like 'Silly Goose'. However, at the age of nineteen, the untimely and gruesome deaths of her entire family completely break her heart and leaves her an orphan. The deaths of her six-year-old nieces were the most difficult for her to accept. Her family's real murderer, Viktor, tricked her into believing that a pack of Lycans were the ones responsible for the killing. And so, Selene dedicates herself to avenging their deaths.
As a Death Dealer (the Vampires' fighting elite), Selene commits herself to the duty of exterminating the Lycans as a species, a duty she sees as 'sacred', burying herself into her work. She also isolates herself, never socialising with anyone outside of the Death Dealers, as the majority of the Vampire Coven are more concerned whiling away their immortal lives in hedonistic pursuits instead of concerning themselves with the serious business of the war against the Lycans.
From Wikipedia (CC BY-SA 4.0).