The 38-year-old actress has recurred as Frank Gallagher's (William H. Macy) long-lost daughter Sammi Gallagher for 10 episodes this season.
Season 4 of "Shameless" currently ranks as the show's highest-rated season yet, averaging 5.5 million weekly viewers across all platforms, which is up 8% vs. last season.
The series was renewed by the premium cable network for a 12-episode fifth season in February for a 2015 premiere along with the Don Cheadle-led comedy "House of Lies," which will be entering Season 4.
Bergl's other TV credits include "Desperate Housewives," "The Good Wife," "Southland," "Gilmore Girls" and the short-lived ABC dramedy "Men in Trees."
"Shameless" continues Sunday nights at 9/8 p.m. CT on Showtime. The season finale is schedule to air on April 6.
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