Growing up as an orphan, Jeong He-Jin didn’t open his heart to anyone.After giving his all to become a cardiothoracic surgeon, he got into an unfortunate accident,after which he woke up not as ‘Jeon He-Jin’ but as ‘Choi GiSeok’.And on top of that, he has to using his skills…?The accident changed his fate drastically…Can he become ‘the Greatest Cardiothoracic Surgeon’ as ‘Choi GiSeok’?"