Channel A's 'Detectives' Trade Secrets' sheds light on the reunion process between a mother in her 80s suffering from severe dementia and her biological daughter, who has lived apart from her for a long time, revealing unexpected emotional turns.

On this episode, the story of a client and his stepmother, who became a family more than 40 years ago, is introduced. Having lost his biological mother early, the client said he felt a mother's love from his stepmother. Meanwhile, the stepmother carried the painful memory of having her biological daughter taken away by her mother-in-law in the past and being driven out of the family.

There was also a legal obstacle. The stepmother had been living with the client's father without divorcing her legal husband. Because of this, even if the stepmother died, the client would have no right to arrange her funeral. The client wanted to find the stepmother's legal family to receive delegation of funeral rights. Even as her memory faded due to dementia, the stepmother never forgot her biological daughter's name, and the client wanted a meeting between her and her daughter for the stepmother's sake.

The detective team, focusing on the fact that the stepmother's legal husband was from Hwanghae Province, searched displaced persons' organizations but achieved no results. They then shifted to finding the biological daughter using a 'special name' as a clue, and discovered a person matching the name and age at a hiking club. After pinpointing her residence and conducting inquiries, they finally found the biological daughter.

However, the reunion was not purely joyful. The biological daughter showed a cold attitude, saying, "Why is she looking for me now when she abandoned me at age 3?" She also poured out her long-held resentment, saying, "Why look for me now after all this time?" and "That's why I've lived such a miserable life." Watching this, Defconn said, "It seems like she carries deep grudges," and Yoo In-na said, "It seems like there was a lump in her heart her whole life." The mother claimed she was 'driven out,' while the daughter claimed she was 'abandoned,' fully revealing the divergent years the mother and daughter had lived with different memories.

Meanwhile, on this episode, Tongdak Cheonsa, the younger brother of creator Chimchakman, appears as a one-day detective. Tongdak Cheonsa, who recently succeeded in losing 22kg, introduced herself as a 'lookalike of IVE's Liz,' drawing a reaction from Defconn, and Kim Poong joked, "Her nickname used to be Tonggeumboui." Tongdak Cheonsa revealed that she has been dating a boyfriend six years younger for five years, and that their first meeting began with an SNS message. She sent a large box to the office saying she would gift desserts her boyfriend made himself, and the moment she felt his sincerity will also be revealed through the broadcast.