Eliot Ness and the Untouchables are out to convict political boss Brian O'Malley and have two witnesses who will testify that he ordered a murder. O'Malley is an old-time politico who never seeks office himself but controls almost every party official that does. Ness' witnesses are living in a hotel under constant police protection but that doesn't stop O'Malley who manages to use a corrupt cop to kill one of them, George Davas. Ness' only remaining option is to find Davas' girlfriend, Julie Duvall, who he learns was also a witness to O'Malley orders. Time is of the essence for the Feds as mobsters for O'Malley are also on hot on her trail.