Gretchen Mol in HBO's 'Boardwalk Empire'

Sarah Burns joins network's Mike White comedy pilot

Gretchen Mol has joined HBO's upcoming drama series "Boardwalk Empire" as a recurring.

Meanwhile, Sarah Burns is set to co-star opposite Laura Dern in Mike White's comedy pilot for the premium cable network.

"Empire," written by Terence Winter and executive produced by Martin Scorsese, who directed the pilot, is set in 1920 at the dawn of Prohibition and chronicles the life and times of Nucky Thompson (Steve Buscemi), the undisputed ruler of Atlantic City who was equal parts politician and gangster.

Mol will play Gillian, a showgirl.

Mol has been hotly pursued for series roles since her starring turn last season on ABC's "Life on Mars." The actress, who recently toplined the feature "An American Affair," is repped by ICM and John Carrabino Management.

White's single-camera comedy, tentatively titled "Enlightened," stars Dern as Amy, a self-destructive woman who has a spiritual awakening and becomes determined to live an enlightened life, creating havoc at home and work.

Burns will play Amy's workplace friend.

The actress, who co-starred in "I Love You, Man," is repped by UTA.