Marissa Cooper is introduced as a rich beautiful socialite in Newport Beach, California whose family (mother Julie, father Jimmy, and younger sister Kaitlin) go through some dramatic changes over the course of the seasons. She is a troubled person before the series begins, with a history of substance abuse and rebellious behavior. This is even evident from the first episode of Season 1 where she is left on her front door by her friends, passed out from drinking. From there, she is detailed to have private emotions due to the number of lost loved ones in her life and lack of understanding from her family and friends. The backstory on her friendship with Summer Roberts showcases it as a powerful bond, forged during the second grade. One of her deepest connections, and having continued and strengthened throughout the years, the friendship is a central element on the show for three seasons. The show significantly focuses on Marissa's on-and-off again relationship with Ryan Atwood as well, which remains a main focus even after her death in Season 3.