Kang Han-Kyeol (Lee Hyun-Woo) is a great composer and gets inspired by the voice of others. He hides his identity from other people. Kang Han-Kyeol meets Yoon So-Rim. She is a female high school student with a great voice and she falls in love with him.
Cha Jin-Wook (Sung Hoon) is a son from a wealthy family. His family runs a large company. Cha Jin-Wook only pursues short term love. He meets Lee Yoo-Mi (Song Ji-Eun) and changes. Lee Yoo-Mi has never had a boyfriend before.
Ryota Takeshima (Masataka Kubota) has followed in his father's footsteps and now works as a prison officer at Kitakanto Prison. He has witnessed corrupt prison officers who tolerates bullying and gambling. Soichi Nakui (Yukiyoshi Ozawa) then becomes the newly appointed prison chief. Soichi gives an order to Ryota, informing him that he will get rid of prison corruption.
Yoo Ji-Na (Uhm Jung-Hwa) has been a popular singer for the past 20 years, but she holds pain inside because of something she abandoned when she was younger. Meanwhile, Jung Hae-Dang (Ku Hye-Sun) began working as a Yoo Ji-Na impersonator to support her family after her father lost his job. She sings on stage at a club and tries hard to mimic Yoo Ji-Na's songs.
Kang Ha-Ri (Kim Joo-Hyun), with her bright personality, works part-time at a stationary store and a nail shop. Min Deul-Re (Jang Seo-Hee) was a popular actress, but she isn't so popular these days. Kim Eun-Hyang (Oh Yoon-Ah) worked as a secretary prior to the birth of her daughter, but she now focuses on raising her daughter.
These three women lose their most loved ones around the same time. Even though they are not related, they rely on each other to get through the tough times.
In 1986, Detective Park Gwang-Ho (Choi Jin-Hyuk) desperately tries to catch a serial killer. He chases after the serial killer and goes through a tunnel. On the other side of the tunnel, Detective Park Gwang-Ho finds himself in the year 2017. The serial killer has resumed the killings that began 30 years ago. Detective Park Gwang-Ho works with Detective Kim Sun-Jae (Yoon Hyun-Min) and Professor of Criminal Psychology Shin Jae-Yi (Lee Yoo-Young) to catch the killer.
Ahn Joong-Hee (Lee Joon) is an actor who used to be a member of an idol group. One day, he appears in front of a family who consists Byun Han-Soo and Na Young-Sil and their 4 children including Hye-Young and Mi-Young (Jung So-Min). Joong-Hee begins to live wth them.