Damian Lewis is returning to Showtime and he's bringing Paul Giamatti with him.

Homeland alum Lewis and Oscar-nominated Giamatti have been tapped to star in Showtime's drama pilot Billions, The Hollywood Reporter has learned.

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 Rhodes (Giamatti), and the brilliant, ambitious hedge-fund king, Bobby "Axe" Axelrod (Lewis).

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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.

The role marks a return to the premium cable network for Lewis, who won a Golden Globe and Emmy for his portrayal of Nicholas Brody on Showtime's Emmy-winning drama Homeland. His credits include Band of Brothers and PBS' upcoming Wolf Hall. The casting comes after Showtime president David Nevins fought hard to keep Lewis' Brody on Homeland after season one when the character was originally envisioned as having a shorter run on the series. He's repped by UTA, Markham Froggatt and Jackoway Tyerman.

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The casting also reunites Giamatti with Koppelman and Levien, who produced The Illusionist, and with Sorkin, whose book Billions inspired HBO's Too Big To Fail. Giamatti's role in the latter earned him an Emmy nomination.

The prolific actor's credits include his Oscar-nominated turn in Cinderella Man as well as an Emmy-nominated role in Downton Abbey. Should Billions go to series, it would mark the actor's first small-screen regular role. He most recently starred in the FX pilot Hoke, which did not move forward. Giamatti is repped by UTA, Perri Kipperman and attorneys Robert Offer and Shelby Wieser.

Email: Lesley.Goldberg@THR.com

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