Episode 4 recap: Lin Mengchen suspected Ye Xiaosheng's identity.

Qi Zeyu took Lin Mengchen to attend a masquerade ball, and coincidentally Ye Xiaosheng also came to the ball on a mission. He bumped into Lin Mengchen on the dance floor, and Lin Mengchen recognized him from the familiar voice and appearance. He was the person who chased after Cao Fang that night, and she was very interested in him. Ye Xiaosheng caused chaos by killing a Japanese person. Lin Mengchen was knocked down by the crowd rushing to escape. Ye Xiaosheng had already reached the door, but when he heard Qi Zeyu calling Lin Mengchen's name, he immediately turned around and lifted Lin Mengchen off the ground.

Qi Zeyu thought that Ye Xiaosheng had ill intentions, so he suddenly smashed a wine bottle at Ye Xiaosheng. As a result, Lin Mengchen didn't have a chance to remove Ye Xiaosheng's mask. Lin Mengchen didn't know why Ye Xiaosheng was chasing after Cao Fang, but she speculated that it must be related to the Lin family massacre. In her state of confusion, she chose to stay overnight at the Qingfeng Clinic. This gave Qi Zeyu, who had ulterior motives towards her, a sense of opportunity. He tried to get close to Lin Mengchen, but she slapped him hard and drove him to sleep in another room.

When Ye Xiaosheng saw that Lin Mengchen hadn't returned home, he immediately found the Qingfeng Clinic. Lin Mengchen deliberately brought up the masquerade ball to test Ye Xiaosheng. Ye Xiaosheng couldn't let Lin Mengchen know his identity, so he had to conceal it. However, during breakfast, he specifically stated that he wouldn't harm Lin Mengchen and also arranged for someone to obtain her favorite watch, which he planned to give to her later.

Ye Xiaosheng wanted to leave the Blood Sacrifice Hall, but the hall master mentioned how fifteen years ago Ye Xiaosheng voluntarily joined the organization to kill a tyrant and expressed his desire to live elsewhere. The hall master requested three months' time for a smooth transition of his work.