Orange Is the New Black is bulking up for season three.

Mary Steenburgen is closing a deal to join the new season of Netflix's original scripted dramedy, The Hollywood Reporter has confirmed.

Details of Steenburgen's character are being kept under wraps.

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The actress broke the news Thursday via Twitter with an enthusiastic tweet.

Very excited to go to my first wardrobe fitting of OITNB! Will I be in orange or black?:) — Mary Steenburgen (@MarySteenburgen) June 12, 2014

Production on the third season is already underway for the women's prison series from creator Jenji Kohan, starring Taylor Schilling. Laura Prepon will appear in every episode in the new season.

Steenburgen is repped by UTA and Management 360.

Season two, which premiered June 6 on Netflix, featured special guest Lori Petty and an episode directed by Jodie Foster. The series was renewed for a 13-episode third season last month.

Email: Philiana.Ng@THR.com

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