Lifetime has found its Marilyn Monroe . Pan Am and The Aviator alum Kelli Garner has been tapped to play the blonde bombshell in the cabler's upcoming miniseries Marilyn, The Hollywood Reporter has learned. In Marilyn , a four-hour miniseries based on J. Randy Taraborrelli's book, The Secret Life of Marilyn Monroe , Garner will topline the drama that explores Monroe's family life and how she succeeded in hiding from an all-too-invasive world. Garner's Monroe is described as a woman who will walk red carpets in shimmering gowns while fighting a battle against demons she's inherited from her mentally ill mother Gladys (Susan Sarandon, Dead Man Walking), whom she loves, hates and wants desperately to save. Here's Lifetime's official description of the mini: "Marilyn is both the personification of sex, whose first marriage ironically collapses because of her frigidity, and a fragile artist who seeks the approval and protection of men. But afte