In an old vintage antique shop in the suburban outskirts, an unsolved vintage wooden cabinet is hidden. The shop owner, Su Yan, is meticulous and skilled in detail reasoning, accidentally discovering that every guest who comes to deposit or look for old objects is closely related to the subtle clues hidden in the wooden cabinet. All seemingly trivial daily remnants and unintentional speech flaws connect the deliberately concealed warm misunderstandings and old puzzles. The series is serialized in five parts, with each part revolving around a clue of the wooden cabinet, layer by layer dismantling serial mysteries. Throughout there are no murder cases or violence, focusing on detail reasoning, psychological profiling, and warm puzzle-solving. The plot is compact and coherent, with foreshadowing running through the entire series.