The assassin Lia is first seen posing as a café waitress spying on the inexperienced, but clever main protagonist Susan Cooper and reporting to her boss.
Later on she attends a club party intending to assassinate to the person Susan is protecting, but is momentarily captured. She makes a run for it and finds herself cornered in a kitchen and must fight her way out.
A skilled fighter, Lia attacks the mostly inept fighter Susan with a knife. In a series of humiliating mishaps Lia is consistently knocked in the head, leaving a gnarly gash on her forehead. After being beat up thoroughly, Lia still comments that she "can't wait" to kill Susan, only to get her own knife thrust through her hand.
In great pain, Lia removes the knife and thanks Susan for giving up her own weapon and attacks again. This time, Susan grabs her from behind and knocks her to the ground.
Pulling her up, Susan pins Lia to a wall and wraps her hands around her neck, placing her under arrest. However, Lia grabs a nearby knife and tries to kill Susan one last time before an unseen assailant (later revealed to be Jude Law's character back from the dead), throws a knife at her, lodging it deep within her chest and killing her. She slumps to the ground, dead.
During most of her time in the film, Lia wears a green jumpsuit, with her long dark hair loose around her shoulders.