UPDATE (12/15): Rossum's resolve appears to have payed off — the actress tweeted yesterday (December 14) that she'll be back to work on the next Shameless season.

Original Post (12/9): Shameless and headstrong: Emmy Rossum is holding up production of one of Showtime's most popular shows until she's paid at least the same salary as male co-star William H. Macy, according to The Hollywood Reporter

THR reports that Rossum, who plays the show's matriarch Fiona, is in a stalemate with the network, and won't move forward to film a likely Season 8 until the financial playing field is leveled. More, she's potentially seeking a greater salary than Macy to compensate for the years on the show during which she's earned much less.

Showtime has yet to officially announce an eighth season, but THR reports that Macy has already signed on again to play alcoholic and addict Frank Gallagher, Fiona's father. Macy has made more than his fellow cast members since the show premiered in 2011.

THR adds that if Rossum succeeds, renegotiations will also be open to the rest of the cast. Still, Showtime could also choose to continue Shameless without her or cancel it outright.

Rossum is one of many high-profile actresses who have spoken out against sexist pay gaps in recent months. Jennifer Lawrence, Dakota Fanning, Jessica Chastain and Mila Kunis are just some who have shared personal stories in of being denied equal pay to male co-stars.

Surprised to hear Rossum is taking such a firm stance on the salary dispute? Share your thoughts in the comments.

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