"Rogue One: A Star Wars Story" might be past its opening weekend, over which it took an impressive $155 million domestically and $290.5 million worldwide, but its seemingly unstoppable Imperial march continues. The first standalone film in the "Star Wars" saga added a further $17.7 million in domestic ticket sales to its already stellar success on Monday.

This figure, which represents the fourth-highest takings for a film showing on a Monday in December, may actually increase when official numbers from Disney are released.

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Ticket sales for the most adult addition to the "Star Wars" franchise to date could be further bolstered later in the week as more school districts embark on their upcoming holiday break.

Set just prior to the events of 1977’s “Star Wars,” “Rogue One” focuses on a ragtag group of Rebels that undertake a dangerous mission to steal the design plans for the Galactic Empire’s new planet-destroying superweapon, the Death Star.

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Directed by Gareth Edwards, the film stars Felicity Jones, Diego Luna, Ben Mendelsohn, Donnie Yen, Mads Mikkelsen, Alan Tudyk, Jiang Wen and Forest Whitaker and is in theaters now.

Via Deadline.com