After returning from a business trip, Jiang Yan accidentally sees his son hugging his friend and calling him Dad. Following the clues, he discovers that his wife has been letting this man take his place for years. The paternity test results are even more devastating: the son he has raised for six years is not his biological child. Jiang Yan knows the marriage can end, and he intends to uncover the truth and reclaim what he is owed. But every time he hears the child calling him Dad, his heart fills with reluctance, making it difficult for him to walk away decisively.