Traveler Without Baggage is about an amnesiac World War I veteran who reinvents his sordid past to give himself peace in the future. Antigone was a rewriting of the ancient Greek tragedy by Sophocles, and deals with the conflict of practical compromise and idealism. It was first presented in occupied France during World War II and was seen as a veiled criticism of the Vichy government that cooperated with the German occupiers.
The Lark was about the French heroine Joan of Arc, and focused on her rejection of authority. Becket was about English martyr Thomas Becket, who was Archbishop of Canterbury until he was murdered by supporters of King Henry II.
His career spanned half a century, and his work changed and evolved throughout his lifetime. He grouped his lighter comedies and fairy tales as his "pink plays" and his darker realistic dramas and tragedies as "black plays." He classified his historical plays as "costume plays."
His work in the 1940s and 1950s, he called his "brilliant plays," which had settings of wealth and grandeur and featured witty dialogue, and his "grating plays," which were more bitter black comedies. Near the end of his life, he wrote what came to be called his "secret dramas," and were far more focused on the theater itself, dealing with the creative process, writer's block, actors and directors.