EXCLUSIVE: The former Law And Order: Criminal Intent star has joined the John Wells-directed film. In August: Osage County Julianne Nicholson will play Ivy Weston, one of the sisters to Julia Robert’s Barbara in the adaptation of Tracy Letts’ Oklahoma family clan play. Ivy is the middle daughter to Violet, played by Meryl Streep. Ivy stayed in Oklahoma and teaches at a local college and is having a secret affair with a man she plans to move to New York with. Nicholson worked with Wells before on the CBS series Presidio Med back in 2002-2003. The actress has appeared recently on CBS’ The Good Wife and on HBO’s Boardwalk Empire. Juliette Lewis plays the youngest daughter Karen in the sibling trio in August: Osage County. Ewan McGregor and Dermot Mulroney are also in the film, as is Abigail Breslin who plays Barbara’s daughter, Jean. Margo Martindale is in the film too as Violet’s sister Mattie Fae. George Clooney and Grant Heslov are producing along with Jean Doumanian, Steve Traxler and Claire Rudnick Polstein. The Weinstein Co. is financing and distributing August: Osage County. Julianne Nicholson is repped by CAA and Davien Littlefield Management.