Mark asks Dr. Jackson Avery to find out how Lexie's doing, but Jackson lies to Mark that he wasn't able to find anything out, and he (Jackson) starts dating Lexie shortly after that. In the meanwhile, Callie and Mark's daughter is born. Mark later gives Jackson and Lexie his blessing, and tells Lexie he will let her go; Lexie replies that she is still in love with him, but right now she needs Jackson to be happy. After giving Jackson a hard time, Mark finally acknowledges his surgery skills and decides to teach him, although he still evidences feelings towards Lexie. After a long time without dating, Mark finally embarks on a relationship with Julia. This makes Lexie jealous, which leads to her and Jackson breaking up. Lexie struggles to tell Mark how she feels but finally admits it, leaving him torn between her and Julia. In the season 8 finale, Mark, Lexie, Derek, Meredith, Cristina, and Arizona are involved in an aviation accident while on the way to Boise, Idaho to perform surgery on conjoined twins, crushing Lexie under debris. After trying and failing to save her, Mark holds dying Lexie by the hand, telling her that he has always and will always love her. He and the remaining surviving crash victims are left stranded in the woods, mourning Lexie and fighting to stay alive.