Reunited Worlds

Hae Sung and Jung Won are ordinary high school seniors who are getting themselves ready for life after graduation. One day, Hae Sung wakes up to find everything surrounding him different. He was dead for 12 years.

Hae Sung looks for ways to figure out what happened to him when he accidentally runs into his high school friend, Ho Bang. Ho Bang visits Hae Sung's tomb every year with the rest of Hae Sung's high school friends. It turns out that Hae Sung was killed on his birthday.

Jung Won is confused and pressured by Min Joon's confession. Hae Sung finds out how his family and friends have been living through Ho Bang, who also tells him that he and the rest of their friends lost touch with Jung Won.

Jung Won takes care of Hae Sung who was injured and lost consciousness. Jung Won thinks she's insane for thinking that Hae Sung has comeback from death. Hae Sung finds out how Jung Won's life has been difficult without him and is heart-broken.

Jung Won decides to let Hae Sung stay at her place. They spend a good time chatting about their past. The next day, Hae Sung finds a way to help both Jung Won and Hae Chul out of the gang's hands. Meanwhile, Hae Sung runs into Young Jun, but Young Jun asks her to keep his family status a secret.

Jung Won tells Min Joon that Hae Sung is her cousin, which doesn't make Hae Sung happy. On their way back home, Hae Sung and Jung Won decide to have a drink together for the first time. Hae Sung honestly tells Jung Won about how he feels about the current situation he is in.

Hae Sung finds out from Jung Won that Young Jun wasn't with her on the day Hae Sung died. The police report was recorded falsely and Hae Sung thinks it's strange. Meanwhile, Tae Hoon, who is the vice president of a department store, tells Hae Sung that Young In works in the department store. Hae Sung meets Young In, only to find out that she's been living a hard life.

Min Joon gets his wrist injured and Jung Won offers to help him. Hae Sung goes over to Min Joon's place and offers to help instead of Jung Won. Meanwhile, Gong Joo disappears from her kindergarten and Hae Chan looks all over the city to find her.

Hae Sung finally meets his youngest sibling, Soo ji. He has met all of them and had a chance to talk to each other except for Young Jun. When Hae Sung visits Young Jun at his hospital to talk, Young Jun tells him to stop acting like his real brother.

Min Joon helps and trains Jung Won into becoming the main chef of his restaurant. However, Jung Won fails the promotion test and does not make it. Disappointed Jung Won meets up with Hae Sung in front of the restaurant and hugs him, only to be discovered by Min Joon.

Ho Bang tells Hae Sung that the driver who hit Hae Sung with his car was also dead. When Ho Bang visited the driver's funeral home, the driver's wife was saying that he wasn't the real killer, which made Ho Bang suspicious. Ho Bang gets transferred to Seoul and the friends gather to send him off.

Hae Sung finds out that Hae Chul got into a fight in the restaurant because someone accused Hae Sung of being a murderer. Mr. Ahn tells Hae Sung that he gets pain in his chest whenever he's near someone who's related to his death. Min Joon gets hit by a car while trying to help Jung Won.