Complex sentence: In the late 1940s and 1950s, he was a stage director in London, where his work included the English première of Jean Genet's "The Balcony" in 1957.
Split into simpler sentences: In the late 1940s and 1950s, he was a stage director in London. His work included the première of Jean Genet's "The Balcony" in 1957.