"Risk hunters" are professionals who handle jobs considered too tough for normal law enforcement, such as kidnappings, combating terrorism, and preventing murders. One man who stands above them all however is the legendary Chameleon Jail, who has the ability to manipulate his "kara" or internal human body energy in order to physically change his appearance into that of any other person.

Throughout the series, he pursues several assignments on behalf of various clients given to him by Shall, a woman who runs a detective agency in New York City. All difficult, the successful completion of these assignments hinges on Jail's ability to change his appearance when the time is right.