He's the 5th artist up to lend his voice for this drama, and his song serves as the theme song for main male lead played by Hyun Bin. The song was composed by VIBE's Ryu Jae Hyun, and its meaningful lyrics as well as the desperation conveyed through Kim Bum Soo's voice will have you listening to it over and over.

Without further ado, give it a go above!