S1·E17 Episode 17

Once Lin Manor is sealed, First Madam divides up which courtyard will house the sick and which will house those who have no symptoms. Lin Xiu Ru confides in Lan Xiang that she had Du Cui Que's maid, Ling Dang, follow; Ling Dang only spoke to two maids carrying bath water, then returned to Cui Que's courtyard. Lan Xiang's roommate also mentions that Lady Du said it was too bad Jin Qi had to leave after his bath. No matter how tired she was, Lan Xiang's mind was working overtime and couldn't let go of all the talk about bath water. She started to wonder whether the epidemic was not contagious but was brought on by poison instead. In the meantime, Lin Jin Qi and the Marquis have their own traps to set to catch those trying to kill them.