Okay so I watched this drama for 1 reason only & of course that reason was bc of Ahn Hyo-seop's beautiful face! I dont nothing bout an original so I cant compare- maybe it wouldve helped me be able to follow the story bc I have no idea what the heck was going on? I think she was able to time travel after listening to a tape inside a walkman and land in another chicks body just bc they looked alike??? Okay so I can somewhat follow that but then they threw in that he also time traveled back into time into the boys body as well??? But they never showed him ever time traveling back??? Somehow he knew it would send her back so he mails the walkman to her in hopes she would go back in time and stop the murders from occurring so they all can live in the future- Han Jun-hee, Koo Yeon-jun, & Si-heon, Min-Ju, & In-gyu...Of course changing the course of the past changes the courses and lives in the future so I get that so how come in the end there was only Jun-hee & Si-heon??? Did the plane crash really happened that took Yeon-Juns life??? My conclusion, I think? is that Yeon-Jun never existed in Jun-hee's future since her entire life wiped away? It wouldve kinda came together more if at the end if Si-heon & Jun-hee introduced themselves on the bus & it took him back to his memory of when he saw her as a little girl when she told yelled her name to him & told him to remember the next time he saw her...I think alot of extra stories & scenes got thrown into this drama that made the story so difficult to follow when it couldve been made clearer by leaving alot of them out. I guess the story is way beyond my intelligence but I do have to admit, none of it took away from Ahn hyo-seop's handsomeness & I totally enjoyed watching him! That was the very best thing bout this drama, hands down!