The drama which is a remake of the same-titled 2004 South Korean drama from KBS starring So Ji-sub, features Nagase as the lead character Okazaki Ritsu who was abandoned by his mother Reiko (Ootake Shinobu) when he was a child. One day, when Ritsu gets embroiled into an incident that causes him to suffer a life-threatening injury, he decides to meet Reiko for the last time and do something for her out of filial piety because he doesn't know when his life will end. However, when he sees how much she loves her son Satoru (Sakaguchi Kentaro) who is a idol pianist and the happy and rich life she has compared to him who is wallowing in the low rungs of society, Ritsu vows to take revenge on her. At the same time, he falls for a woman Mita Rinka (Yoshioka Riho) who helps him by chance but he is sad to find out that she is in love with his half-brother who is Rinka's childhood friend. Lee will be playing the role of Baek Ran who is the heir of a Korean mafia chief and admires Ritsu like an elder brother. Baek Ran was abandoned by his birth parents at an orphanage soon after he was born and became the adopted son of a couple who later went to South Korean. Later, Baek Ran left home to join the underworld and met Ritsu who works as a bouncer at the casino owned by his father. Baek Ran's presence becomes a trigger as to why Ritsu returns to Japan to look for his mother.
At the staff members' suggestion, Nagase and Kamiya did their recording not in the usual recording booth but while surrounded by the staff. Although Kamiya commented that he was not used to doing it this way with people around him, he managed to get through the recording very easily true to his reputation as a top voice actor and finished well ahead of schedule. Upon seeing this, Nagase expressed his admiration for Kamiya who became one with Lee's character even though they are clearly two different individuals and that Kamiya paid so much attention to detail while doing the voice-over. Kamiya also praised Nagase for doing a good job as his Japanese lines seemed to fit seamlessly with the Korean he was speaking in the drama and that the latter is such a versatile actor to be able to do this effortlessly.