After ten years in prison, a thief tries to adjust to improved surveillance methods.

Released from prison after serving a ten-year sentence for robbery, unregenerate safecracker Robert "Duke" Anderson immediately seeks out his former mistress, Ingrid Everleigh, who resides in a luxury apartment house in New York's fashionable Upper East Side. Despite the building's television security system, Anderson develops a master plan to rob all the wealthy occupants on the same day, Labor Day. Unknown to Anderson and Ingrid, monitoring agency "Peace of Mind," hired by Ingrid's jealous benefactor Werner, has bribed doorman O'Leary to allow it to install monitoring equipment in the building's basement so that it can bug Ingrid's apartment. Later on the phone, Ingrid breaks up with Werner and tells Anderson that, although he can stay with her, she does not wish to know about the heist. Anderson then attempts to secure financing through his old connections to Mafioso Pat Angelo, but does not realize that Angelo is also being monitored by the Treasury Department because of his mob connections. Later, Anderson visits his old friend, antique dealer Tommy Haskins, who is also being secretly monitored by the FBI for fencing stolen goods, to ask him to assess and mark the targeted apartments' antiques. When Anderson goes to the apartment of Spencer, a black ex-convict, to hire him as a getaway driver, he is filmed by the building's surveillance cameras, which have been monitoring Spencer to see if he is associating with Black Panthers living in the building. As scheduled, days later, Tommy enters Ingrid's building claiming to O'Leary that the management has hired him to redecorate the halls. At the same time, electronics expert The Kid, who served prison time with Anderson, poses as an electrical repairman to gain access to the alarm system. Meanwhile, Spencer arrives with a mink stole to be delivered to Ingrid. O'Leary, suspicious of Spencer because he is black, escorts him to 2B, where Ingrid goes into the bedroom to try on the coat. Anderson, who is hiding in the bedroom, asks her to detain O'Leary for another eight minutes, leaving enough time for Tommy to finish gaining access to each apartment through his ingratiating manner. Later, Angelo arranges to meet with Anderson in his limousine during a funeral procession, but an IRS agent, dressed as toll booth taker, plants a device under the car, thus recording their conversation as Anderson explains to Angelo that the heist is worth several million dollars. Angelo, now trying to appear to be a respectable businessman, is torn between his allegiance to his old friend and his current life. Claiming that he needs the approval of elderly mob boss Papa Angelo, Angelo drives to Papa's mansion, leaving Anderson in the car. Angelo then debates out loud with himself about whether to support Anderson, as Papa, who is suffering from dementia, is unable to comprehend the situation. Meanwhile, the IRS has planted a pen with a concealed microphone on Papa's nurse, thus recording his description of Anderson's heist. Angelo finally agrees to give Anderson $17,000, on the condition that he take along hit man Socks Parelli and kill him during the heist. When the whole group meets later, Spencer threatens to leave because he fears the bigoted Socks, who has already threatened them, cannot be controlled. While Jimmy, whom Spencer has hired as another getaway driver, detains Socks outside, Anderson explains to Tommy, Spencer and The Kid that he must kill Socks as part of Angelo's deal. Though disturbed by the violence now involved, the three agree to go ahead. Soon after, Anderson returns to 2B to find Werner playing a recording of Anderson and Ingrid in bed. Werner insists that he have exclusive rights to Ingrid, and although Anderson offers to cancel the heist if she stays with him, Ingrid accepts Werner's arrangement for fear of losing her financial security. Werner tells Anderson that he will not interfere with the robbery, as a crushed Anderson leaves the apartment. On Labor Day, Anderson and the others steal a large moving truck and load a panel van and other equipment into it. They then pick up Tommy, Socks and William "Pop" Myer, another fellow ex-convict, whom Anderson hired out of pity for the old man, who has had trouble adjusting to civilian life after spending over thirty-five years behind bars. Arriving at the building, the thieves tie up O'Leary and put him in the basement, then station Pop, now wearing the doorman's uniform, at the front desk. Anderson and others, wearing masks, rob Dr. Rubicoff in his office, and then they rob Mrs. Hathaway, an elderly but spirited woman who is more excited about the adventure of the heist than her valuables or the well-being of her companion Miss Kaler. Soon after, Socks beats Rubicoff mercilessly, until Anderson stops him and then warns the victims that Socks will hurt them unless they do as he asks. Soon after in the Bingham apartment, Anderson discovers young Jerry Bingham, a paraplegic, behind a locked door. Assuming the child cannot move, Anderson leaves him alone, but Jerry alerts the police on his ham radio. Soon after, one of the tenants arrives with his boyfriend, prompting Anderson and The Kid to lead them at gunpoint to an apartment where the others are being held. Meanwhile, around the corner from the building, dozens of police, led by Captain Delaney, are waiting to apprehend the robbers. Wanting to flush out Anderson and the others, Delaney sends Sgt. Everson and several men to gain access from the roof. Meanwhile, when Anderson, now at the Longene apartment, the last on his list, threatens to hurt Logene's wife if he does not open his safe, the smug man refuses and then suggests to his horrified wife that she "be brave" in order to save their valuables. Desperate, Anderson calls in Socks, who easily convinces Logene that he will kill him. As they finish the job, Anderson hears Everson and his men's footsteps on the roof and races to lock the stairwell doors to prevent them from entering. Rushing to the apartment in which the victims are being held, Anderson looks outside, and seeing no pedestrians or cars on street, realizes that the police have stopped traffic and surrounded the building. Losing his nerve, Tommy decides to wait there and turn himself in. When Socks suggests they use the hostages as human shields, Anderson kills him. Alerted by the gunfire, Everson busts through the doors and, in the ensuing gunfight, wounds Anderson. The Kid, Jimmy and Spencer attempt to flee in the moving van, but the police kill them. Meanwhile, Anderson hides in the chimney in Ingrid's apartment, while Pop, tired of being in the outside world, turns himself over to Delaney in hopes of returning to prison. Hearing groans on the recording equipment in the basement, the police find Anderson in 2B and rush the badly wounded man into an ambulance. After the newspapers name Anderson in the attempted robbery, all the various agencies who monitored the people involved in the heist immediately have the tapes erased to avoid being prosecuted for obtaining evidence illegally.