how did she die in the series?
Plane crash
Lexie Grey
plane crashes
when do mark and lexie die in grey's anatomy In season 8, While flying with fellow surgeons to separate conjoined twins. how is she related to meredith grey? She is her  younger paternal half-sister. when was she first introduced in the series? Season three who plays her character? Actress Chyler Leigh. what response did her character receive? Chyler Leigh's performance garnered positive feedback and acclaim as her role on the series progressed, and Lexie soon became a favorite of critics and fans of the show.
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Lexie Grey [SEP] Season 8
Days later, Lexie is named as part of a team of surgeons that will be sent to Boise to separate conjoined twins, along with Mark, Meredith, Derek, Cristina and Arizona Robbins (Jessica Capshaw). While flying to their destination, the doctors' plane crashes in the wilderness and Lexie is crushed under debris from the aircraft but manages to alert Mark and Cristina to help her. The pair try in vain to free Lexie, who realizes that she is suffering from a hemothorax and is unlikely to survive. While Cristina tries to find an oxygen tank and water to save Lexie, Mark holds Lexie's hand and professes his love for her, telling her that they will get married, have kids, and live the best life together as they are "meant to be".