'The West Wing' actress Mary McCormack is boarding 'House of Lies'.
McCormack, 45, will play major investor Denna Altshuler in the Showtime comedy series, according to Deadline.
Denna Altshuler will come to the aid of Marty Kaan (Don Cheadle) just as it looks like Kaan & Associates is near ruination.
McCormack is a two-time Screen Actors Guild Award nominee for her portrayal of US national security official Kate Harper in 'The West Wing'.
She more recently portrayed US marshal Mary Shannon in 'In Plain Sight'.
Alicia Witt ('Friday Night Lights') will appear in the new season as well as an engineer hired by Marty Kaan.
