After the Communist Party of China won the Civil War and established the People's Republic of China in 1949, Wu returned to Beijing. Like many intellectuals at the time, he held high hopes for the new People's Republic which finally restored peace in a united China after decades of war and division. He wanted to return to writing plays, but was assigned by the government to direct Song of the Red Flag, a film about women textile workers. As he had no experience with factory life, it took him a year to finish the film, which he considered a "worthless failure." He and Lü En divorced amicably in 1950, due to differences in personality and interests.
