“I regretted all my decisions in life.” After serving 10-year prison sentence, Su-hyuk (JUNG Woo-sung) learns that he has a daughter and decides to leave the syndicate he called home to live a normal life. Boss Eung-kook (PARK Sung-woong), who had been waiting for Su-hyuk's release, feels betrayed and orders his second-in-command, Kang (KIM Jun-han), to keep an eye on him. Filled with a sense of inferiority towards Su-hyuk, Kang approaches the duo of assassins known as Woo-jin (KIM Nam-gil) and Jin-ah (PARK You-na), nicknamed ‘The Washer’, to eliminate Su-hyuk. These merciless assassins handle their targets in their own brutal ways, and they get closer to killing Su-hyuk... A normal life becomes the most dangerous dream.