A team of infiltrators from the triad penetrated the police force. However, the police also has sent a team of undercover agents to infiltrate the triad. Ten years later, they are still undercover, but their minds have been twisted by the temptation of power, authority and money — and nobody is certain about their original roles anymore. Both groups learn that they have been infiltrated and want to ferret out the moles. Each mole has a secret code to lock their identity file, and once the code is cracked their identity is fully revealed. The battle of wits starts now. Either exposing the enemy or taking the chance to change the identity for good can save their lives as long as nobody knows who is who!