Ron Livingston Cast as Series Regular on Boardwalk Empire Season 4

Ron Livingston has joined the cast of Boardwalk Empire.

The beloved Office Space actor will be a series regular when the HBO drama returns, coming on board as an out-of-town businessman who arrives in Atlantic City and strikes up a relationship with Gretchen Mol's Gillian Darmody.

Livingston has appeared in Band Brothers, Game Change and romanced Carrie Bradshaw for a bit back in the day on Sex and the City.

Boardwalk Empire will premiere Season 4 some time this fall, likely in September.

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