This is a story about the struggle faced by a lawyer from a lower class. He is willing to do anything to protect himself and his loved ones in a world where most people are driven by selfish interests. Pak Chang Ho is trying to build a career as a lawyer, but can only boast a 10 percent success rate so far. He loves to talk, which is why people call him "Big Mouth." One day, the hero becomes involved in a murder case and is unexpectedly mistaken for a brilliant criminal. From that moment on, the lives of Pak Chang Ho and his family are in danger...