Nirvana in Fire Episode 17

Qin Banruo advises Prince Yu to make the gunpowder case a bigger issue to give a bigger blow at the Crown Prince. Before the factory is closed down, Prince Yu explodes the building, causing many civilian deaths and injuries. Prince Jing arrives with his troops to aid the people; Mei arranges the prince to not follow protocol so that people would see Prince Jing's good deeds. After hearing Shen Zhui's testimony, the Emperor permanently grounds the Crown Prince. Prince Xian also fails to get Prince Jing punished, as many officials in the court support him, instead of the Xian's Ministry of Defense. Mei invites guests, to his newly renovated home, and devises a game, where the guests must find a musical score in the house. Qin Banruo finds his secret room. (Source: Wikipedia)