The preeminent writer’s theater, it has fought censorship and unveiled international brilliance for so long that it’s now a preeminent actor’s theater as well. On the east side of jaunty Sloane Square, it devotes a hefty portion of its schedule to important premieres by the likes of Bruce Norris and Caryl Churchill to performances from fierce actors such as Ben Whishaw and Fiona Shaw. Among the plays launched here include Look Back in Anger, The Rocky Horror Picture Show (in its upstairs studio theater), George Bernard Shaw’s Major Barbara and Heartbreak House, and Mike Bartlett’s Cock.