One member of a gang that robbed more than $1.8 million has been arrested in St. Louis. Under questioning from Erskine and Colby, he reveals the names of two other members of the gang but says he doesn't know the identity of the mastermind behind the holdup. The gang only knew him as "the salesman." The FBI apprehends another gang member in St. Louis. Meanwhile, the last member has figured out "the salesman" is in San Diego. The FBI, under Erskine's direction, also now seeks the mastermind in San Diego. The question is who will reach "the salesman" first.