Terminator: Dark Fate marks the return of Linda Hamilton as franchise protagonist Sarah Conner for the first time since 1991's Terminator 2: Judgment Day.

In preparation to reprise the action role, Hamilton worked out steadily for a year and avoided consuming carbohydrates. However, despite being in excellent physical condition, the training caused Hamilton to become so lean, the costume designers decided to mold a fake posterior for her costume, as revealed by the actor on The Graham Norton Show.

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Hamilton underwent a similar physical transformation for Terminator 2, becoming a lean, muscular figure reflecting the character spending years training and honing her skills to prepare for the coming robot apocalypse.

Dark Fate was screened for professional critics earlier this month, with advance reactions from the screenings largely positive, praising Hamilton and co-star Mackenzie Davis' respective performances in the film. What's more, some have gone as far as to label it as the best installment in the sci-fi franchise since the original two films.

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Directed by Tim Miller and produced by James Cameron, Terminator: Dark Fate stars Arnold Schwarzenegger, Linda Hamilton, Mackenzie Davis, Gabriel Luna, Natalia Reyes and Diego Boneta. The film opens Nov. 1.