But Roland isn't the only major role that Howard needs to fill. There are other integral players from the nefarious Man in Black to recovering drug addict Eddie Dean. Then, of course, there's Susannah Dean.

King has said before that he always envisioned Angela Bassett as an ideal actress for Susannah, but given Bassett's current age, her casting doesn't seem likely. It seems especially unlikely given a new rumor that the part of Susannah is Naomie Harris' for the taking.

The New York Post has the rumor, stating quite simply and without attribution: "'Pirates of the Caribbean' beauty Naomie Harris is being considered for the female lead in the Ron Howard's eagerly anticipated 'Dark Tower' trilogy." Without any official confirmation, let's treat Harris' involvement as a rumor for now — but it's certainly a rumor we're excited about.

In the novels, Susannah Dean is originally known as Odetta Holmes and Detta Walker, two wildly different women trapped within the same body. After suffering a serious brain trauma early in her life, Odetta's damaged mind created the Detta personality, a cold-blooded and violent racist with intentions of killing both Roland and Eddie. Eventually, Roland successfully fuses the legless woman's two personalities into the solitary Susannah Dean, turning her into an invaluable member of his Ka-tet of gunslingers.

There's a lot of material to play with for whoever lands the role of Susannah, and I really do think Harris would nail it. Despite her sweet-faced demeanor, Harris has proven herself capable of wild and outrageous performances like Tia Dalma in the "Pirates of the Caribbean" series. There's no doubt she's got shades of Detta inside of her, and if she can combine that ferocity with the sweetness of Odetta, Harris would make for a killer Susannah.

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