Deadline.com reports that Lathan is currently finalizing a deal to play Mona, "Kane’s incorruptible new chief of staff, who becomes an obsession for him." Groff will play the role of Ian Todd, "a smart and ambitious staffer in Kane’s office who steps into the void Ezra Stone (Martin Donovan) has left to offer astute council to Kane."

Jonathan Groff received a Tony nomination as well as a Theatre World Award for his performance in Broadway's Spring Awakening. His Off-Broadway credits include Spring Awakening, Hair, The Bacchae, Prayer for My Enemy and The Singing Forest. He was also seen in the West End in the revival of Deathtrap. Groff's screen credits include "Taking Woodstock," "The Conspirator," "Twelve Thirty," "Glee," "One Life to Live" and "Pretty/Handsome."

Lathan recently starred as Maggie the Cat in the West End revival of Cat on a Hot Tin Roof and Off-Broadway in By the Way, Meet Vera Stark. Her previous theatre credits include Beneatha Younger in A Raisin in the Sun with Sean Combs (Tony Award Nomination for Best Performance by a Featured Actress); Isabella in Measure For Measure opposite Billy Crudup at The Public Theater's Shakespeare in the Park; Emily Webb in Our Town at South Coast Repertory; Por'knockers at The Vineyard Theater; A Movie Star Has To Star In Black and White at the Public Theater; and Viola in Twelfth Night at Yale Repertory Theater. Her film credits include the upcoming Steven Soderbergh film "Contagion," opposite Matt Damon and Kate Winslet, opening in October, "Wonderful World" opposite Matthew Broderick, "The Family That Preys" with Tyler Perry, "Something New" (NAACP Image Award Nomination), "Alien vs. Predator," "Out Of Time" opposite Denzel Washington, "Brown Sugar" (NAACP Image Award Nomination), "Love and Basketball" (BET Award, NAACP Image Award), and "The Best Man" (NAACP Image Award Nomination).

"Mayor Tom Kane (Kelsey Grammer) sits like a spider at the center of Chicago’s web of power; a web built on a covenant with the people," according to production notes for the series. "They want to be led, they want disputes settled, jobs dispensed, and loyalties rewarded. If he achieves through deception and troubling morality, so be it. As long as he gets the job done, they look the other way. Yet despite being the most effective mayor in recent history, a degenerative brain disorder is ripping everything away from him. He can’t trust his memory, his closest allies, or even himself."

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