A Sons of Anarchy favorite is riding to Showtime.

Maggie Siff, who portrayed Tara for six seasons on the FX biker drama, has boarded the cast of drama pilot Billions, Showtime announced Monday.

Billions is a fictional drama that takes a forensic look at the world of high finance by tracking the approaching collision between two titanic figures — the hard-charging, whip-smart U.S. Attorney Chuck Rhoades (Paul Giamatti), and the brilliant, ambitious hedge-fund king, Bobby "Axe" Axelrod (Homeland's Damian Lewis).

Read more Showtime Orders Drama Pilot From New York Times' Andrew Ross Sorkin

Siff will play Wendy Rhoades, Chuck's wife. After graduating at the top of her medical school class and training as a psychiatrist, she is now a highly in-demand performance coach who works with some of the most powerful and influential figures in the world of high finance.

Billions is written and executive produced by Brian Koppelman, David Levien and Squawk Box's Andrew Ross Sorkin, and was picked up to pilot in March. Neil Burger (The Illusionist, Divergent, Limitless) will direct the pilot, which will film in New York in early 2015.

Siff's credits also include Mad Men and features Concussion, Leaves of Grass, Funny People and the upcoming The Fifth Wave. Siff is repped by Paradigm and Suskin Management.

Email: Lesley.Goldberg@THR.com

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