Tae Gun-ho (Jung) is the best collection agent in his firm, admired by his colleagues and dreaded by those he visits. He's known for gathering his debts by any means necessary, and keeps a cattle prod handy while on the job. Following a series of unexpected fainting spells, Tae is told by a doctor that he has liver cancer, and would need a transplant to have any chance of surviving beyond three months. And so he puts his professional skills to work, setting out to collect a different sort of debt by tracking down the recipients of organs donated by his late son. First among his sources for a liver is Cha Ha-yeon (Jeon), a beguiling fraudster with a long list of enemies.