George Orson Welles was born May 6, 1915, in Kenosha, Wisconsin, son of Richard Head Welles (b. Richard Hodgdon Wells, November 12, 1872, near St. Joseph, Missouri; d. December 28, 1930, Chicago, Illinois) and Beatrice Ives Welles (b. Beatrice Lucy Ives, September 1, 1883, Springfield, Illinois; d. May 10, 1924, Chicago).

Simultaneously with his work in the theatre, Welles worked extensively in radio as an actor, writer, director and producer, often without credit. Between 1935 and 1937 he was earning as much as $2,000 a week, shuttling between radio studios at such a pace that he would arrive barely in time for a quick scan of his lines before he was on the air. While he was directing the Voodoo Macbeth Welles was dashing between Harlem and midtown Manhattan three times a day to meet his radio commitments. In addition to continuing as a repertory player on The March of Time, in the fall of 1936 Welles adapted and performed Hamlet in an early two-part episode of CBS Radio's Columbia Workshop. His performance as the announcer in the series' April 1937 presentation of Archibald MacLeish's verse drama The Fall of the City was an important development in his radio career and made the 21-year-old Welles an overnight star. In July 1937, the Mutual Network gave Welles a seven-week series to adapt Les Miserables. It was his first job as a writer-director for radio, the radio debut of the Mercury Theatre, and one of Welles's earliest and finest achievements. He invented the use of narration in radio. "By making himself the center of the storytelling process, Welles fostered the impression of self-adulation that was to haunt his career to his dying day," wrote critic Andrew Sarris. "For the most part, however, Welles was singularly generous to the other members of his cast and inspired loyalty from them above and beyond the call of professionalism." That September, Mutual chose Welles to play Lamont Cranston, also known as The Shadow. He performed the role anonymously through mid-September 1938.

Answer the following question by taking a quote from the article: Which show was he most famous for?
drama The Fall of the City was an important development in his radio career and made the 21-year-old Welles an overnight star.