Sanaa Lathan and Glee heartthrob Jonathan Groff have landed new regular roles on the second season of Starz’s drama series Boss. The Lionsgate TV-produced series stars recent Golden Globe winner Kelsey Grammer as ruthless Chicago mayor Tom Kane. Lathan is finalizing a deal to play Mona, Kane’s incorruptible new chief of staff, who becomes an obsession for him. Lathan, repped by ICM and John Carrabino, voices the female lead on Fox’s The Cleveland Show and was most recently seen in the feature Contagion. Groff will play 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. WME-repped Groff is best known for his recurring role as villain-turned-good guy Jesse St. James on the Fox musical dramedy Glee.