Blade of the Lost

Mother Mu Qin discovers the human trafficker who stole her daughter and goes undercover as a nanny at the trafficker's home to find her. When her investigation is discovered, she and her adopted daughter Cheng Nian are put in danger. Cheng Nian accidentally kills the trafficker Wei Shanren. To clear Cheng Nian's name and find Wei's superior, Mu Qin begins to cooperate with police officer Zheng Xiang. Through their collaboration, they develop a deep friendship, but Zheng Xiang remains focused on his duty and eventually uncovers the truth.