Love's sweet sorrow forms the dramatic storyline for this mystery drama. A free–spirited young woman, Yukari, touches those around her with a zest for life, full of passion. Following her unexplained suicide, her envious younger sister, Reiko, and naive fiancé, Yoshio, form an unlikely alliance with the last person to see her alive, playboy-entertainer Hajime. The three unlikely comrades must join forces to discover the circumstances surrounding Yukari's sudden death. The answers they seek may be found in the many phone numbers stored in her mobile phone. One by one they must interview the people Yukari associated with, to unravel the mystery surrounding her untimely demise. However, the truth may contain more questions than answers. As Yukari's hidden past is revealed, her secret life promises to shock and surprise those who thought they knew her best.