"Sometimes I just want to give up you know? Because it's too difficult when everything feels out of zone. Like you're drowning, except you're awake the whole time and you can't do anything about it."

"Why don't you?"

"Because there was never a choice."

"But there's always a choice."

"Not with a heart like mine."

We have two eyes, two ears, two legs, two hands, but only one heart because the other half is for you to find. Suho's part of the team of top notch doctors in Seoul's best hospital. He trains the new interns, the brightest of Seoul's medical classes.

Together, the twelve are Exo, renowned doctors curing the impossible. Treating special cases is part of his job scope, but he was never taught what to do when you fell in love with a patient. She is a music major who fainted while attending her piano exam. Referred to Seoul's best hospital, her case is the most baffling ever known. They spend their time trying to solve it, but no one said love was part of the package.

Suho knows the solution and it's a heart transplant. But what if, what if that pair to your heart is someone else? They have no choice, but to fall in love all over again.

Can a heart error be righted with true love?