The hectic schedule of rising star Seth Numrich Convincing a rising Broadway star to star in a small, 99-seat Los Angeles stage production can be a real casting coup. But the producers of "Slipping," now running at the Lillian Theatre in Hollywood, have learned that it can also create a major headache. Seth Numrich - already a Broadway veteran at age 26, having played the lead roles in "War Horse" in 2011 and "Golden Boy" this winter - began performances in "Slipping" on Saturday. He plays the main role of Eli, a moody high school student adjusting to life in a small, Midwestern town. The run of the play is scheduled to end May 5, but Numrich will leave the show this weekend - just one week after it officially opened - to head to London, where he was recently cast in the Old Vic's revival of Tennessee Williams' "Sweet Bird of Youth," starring Kim Cattrall. "Youth" will be directed by Tony Award-winner Marianne Elliott, who worked with Numrich on "War Horse" in New York. The actor's last performance in L.A. will be Saturday night. Producers have added a Saturday matinee performance to give the public one additional chance to see the actor. The production will continue with Wyatt Fenner taking over the role of Eli. Fenner recently appeared in Samuel D. Hunter's "The Whale" at South Coast Repertory. In recent weeks, Numrich had been juggling "Slipping" with the shooting demands of the television pilot "Turn," a Revolutionary War-era drama for the AMC cable network. He has shot scenes for the pilot on weekdays in Virginia and flown back to L.A. on weekends to work on the play. Like many small L.A. theater productions, "Slipping" is performed only Thursdays through Sundays. The demands of "Turn" required the play's producers to delay the opening for about a week. Review: 'Slipping' a powerful study of bigotry at Lillian Theatre A spokeswoman for the play said that Numrich had committed to the stage production before he knew his shooting schedule for the pilot. Numrich previously appeared in "Slipping" in 2009 in New York in a production by the Rattlestick Playwrights Theater, which is producing the show in L.A. Juggling stage and Hollywood commitments at the same time isn't unheard-of for actors. Earlier this year, Jessica Chastain missed a handful of performances of "The Heiress" on Broadway to promote the movie "Zero Dark Thirty" and attend awards shows. But leaving a play in the middle of its run to take another stage job is rare. Numrich was unavailable for comment this week because he was shooting "Turn" in Virginia. In a sit-down interview last month, he said he had agreed to do "Slipping" because of his friendship with playwright Daniel Talbott and his relationship with the Rattlestick, where he has appeared in a few productions. Talbott declined to speak about the actor's scheduling but said that Numrich has worked hard to make the play happen. "He virtually did not sleep for 48 hours so that he could open the show," said Talbott in a separate interview. The playwright has formed a theater company with Numrich and said he plans to work with the actor again in the future. Producers of "Slipping" haven't changed the closing date of May 5. The play is the first West Coast production of the Rattlestick, which has gained prominence in New York in recent years as a producer of new plays by edgy writers.