The U.S. Treasury Department is on the trail of a high-grade counterfeit ring, determined to trace the source, the plates, and the people behind the forging. A counterfeiter in prison, Tris Stewart, agrees to an early parole under a staged jail break, staying under supervision so he can help pinpoint the others involved and the plates that years ago belonged to him. This setup aims to lure out the remaining operatives without tipping off the group, turning a risky gambit into a possible breakthrough in a case that could topple an entire network.
Yet Stewart betrays the arrangement and escapes from the supervising agent, and the Secret Service, already ahead of the game, has zeroed in on Stewart's girlfriend Laurie Fredericks in Los Angeles and has bugged her apartment. In parallel, undercover agent John Downey, known to the world as Johnny Hackett, has taken a steady seat in the restaurant where Fredericks works, posing as a wealthy but shady suitor in a bid to keep tabs on her and any talk of the scheme.
Stewart arrives to move in with Fredericks and soon learns that his old partner has sold the plates to Jack Sylvester, now ruined and bankrupt. He visits Sylvester and proposes to buy $250,000 in counterfeit $20 bills, planning to exchange for $25,000 cash. He contemplates robbing the restaurant where Fredericks works; the federal agents overhear and realize the risk to their key operative, prompting a rapid response to prevent a catastrophe.
A police car soon appears, Stewart is arrested, and Hackett makes sure that he is released, enabling him to approach the thankful Fredericks once more. Stewart turns to Hackett, offering to make him very rich if he will stake the money, and the lure of easy wealth adds a dangerous edge to the operation.
After Sylvester meets Hackett and a trial-run exchange involving a box of plain paper, Stewart and Hackett wait for Sylvester to arrange the real transaction. But Hackett's cover is blown when, in the restaurant, an old acquaintance recognizes his identity and Fredericks overhears the man discussing Hackett's résumé, threatening to unravel the whole ruse.
Upon finding out Hackett is a “cop,” Stewart makes a crude attempt to kill him but fails and lands back in custody. Given this, Hackett decides to push through the sale transaction quickly. He picks up Sylvester and the two head for Sylvester's printing press location. Sylvester notices they are being tailed, and Hackett is forced to lose his backup agents who were shadowing their car. At the location, a large box of bills is handed to Hackett and he must stall, waiting for his backup to locate them. But then Fredericks arrives with Sylvester's employee and Hackett's cover is blown again, tightening the noose around the operation.
Meanwhile, outside, a motorcycle officer identifies Hackett's car, and his call allows the agents to locate the warehouse. Inside, Sylvester shoots Fredericks, remarking that if her boyfriend Stewart co-operated with the authorities, however briefly, so might she. He then turns his gun on Hackett, who quickly flips a table toward him and makes a run for it. Police and agents swarm in, upon which Sylvester flees. A chase ensues within a nearby streetcar barn, where Sylvester meets his end by electrocution. The case is marked “closed.”
