In which episode did Wang Zhaojun meet the emperor?

In the first episode of 19, the queen learned that the emperor was looking for a pianist and rushed to the court. When she saw the tall and beautiful Wang Zhaojun, she was afraid of being discovered by the emperor and immediately sent her to the ancestral temple for sacrifice. So in the first 19 episode, Wang Zhaojun met the emperor. Wang Zhaojun is the protagonist of Zhaojun, a great woman who is willing to bear the burden of humiliation for the sake of national justice.