Jonny Lee Miller will join the previously announced Sienna Miller (no relation) in the Roundabout Theater Company’s Broadway production of “After Miss Julie.”

He will play the valet of a rich young woman portrayed by Sienna Miller in scribe Patrick Marber’s retelling of Strindberg’s “Miss Julie.” Both thesps make their Broadway debuts with the show.

The actor (“Trainspotting”) starred for two seasons as the title character in ABC skein “Eli Stone.” London stage credits include “Democracy,” “Beautiful Thing,” and West End incarnations of “Festen” and “Someone Who’ll Watch Over Me.”

Mark Brokaw, who helmed the Roundabout’s recent Off Broadway production of Lisa Loomer’s “Distracted,” directs “After Miss Julie.” Design team includes Allen Moyer (sets), Michael Krass (costumes), Mark McCullough (lights) and David Van Tieghem (original music and sound).

Marber’s version of “Miss Julie” relocates the 1888 Strindberg drama about sex and class to an English country house in 1945, on the eve of the liberal Labour Party’s landslide victory in a general election. After it originated as a 1995 teleplay, “After Miss Julie” had its legit preem at London’s Donmar Warehouse in 2003.

The Broadway staging, which begins previews Sept. 18 ahead of an Oct. 22 opening at the American Airlines Theater, is produced by the Roundabout in association with Sonia Friedman Prods. and Ostar Prods.