A gang of South Korean thieves team up with a Hong Kong crew to steal a diamond necklace from a heavily-guarded casino safe in Macau. As the cops close in, old betrayals — and misunderstandings — resurface.

Jang Tae-Young (Kim Soo-Hyun) is a popular trouble shooter in the criminal world. He is cold and ambitious. He dreams of building a casino hotel one day. A reporter then goes to Jang Tae-Young.

Oh Mal-Soon (Nah Moon-hee) is a 74-year-old widow that realizes she is becoming a burden on her family. As she is roaming the streets, she comes across a photo studio and decides to dress up for a self- portrait. When she walks out of the photo studio, she mysteriously turns back into her twenty year old self. Making the most out of this one in a lifetime opportunity, she changes her name to Oh Doo-Ri (Sim Eun-kyeong) and decides to make the most out of her youth.

As a North Korean sleeper cell agent, Ryu-han infiltrates the South and assumes the role of a village idiot in a rural town. He observes the townsfolk and waits patiently for his mission. One day, after 2 years of playing the role of the village idiot, fellow elite spies Hae-rang, posed as a rock star and Hae-jin, posed as an ordinary student, are dispatched to the same town as Ryu-han. He helps the other two spies settle in and teach them how to adjust in the South. There is a sudden drastic political power shift in the North and all three spies receive an urgent and ultimate mission.