After narrowly escaping a routine burglary, master safe-cracker Nick Wells decides that it’s time to finally leave his life of crime behind and concentrate on his jazz club. His girlfriend, flight attendant Diane, supports this decision, promising that she will invest fully in their relationship if he chooses to go straight. However, the temptation of one last job proves too strong for Nick when his connection, Max, convinces him to take on a lucrative heist that could yield a staggering $4 million. Their target is a priceless French scepter, precariously smuggled into the U.S. and currently held at the Montréal Customs House.
In his quest for this job, Nick enlists the help of Jack Teller, an overly ambitious, yet reckless thief who has ingeniously posed as an intellectually disabled janitor named Brian to infiltrate the Customs House and obtain crucial security details. Nick also brings on board his associate Steven to hack into the security system and acquire the bypass codes necessary for the job. However, when Steven is caught by a sharp systems administrator, he finds himself in a bind, extorted for $50,000 to keep the information secret.
As complications arise due to increased security measures—such as added CCTV cameras triggered by the growing attention on the scepter—Nick and Jack are forced to rush their heist. Using a sewer tunnel, Nick sneaks into the basement while Jack utilizes the bypass codes to disable the cameras. During the heist, Jack's cover is blown when a janitor realizes he is not who he claims to be; however, in a moment of desperation, Jack locks the janitor in a closet.
While Nick masterminds the heist by filling the massive in-floor safe containing the scepter with water before detonating a depth charge, Jack takes the opportunity to double-cross him. At gunpoint, Jack demands Nick hand over the scepter. Reluctantly, Nick submits and, just moments later, the alarm Jack rigged goes off, triggering a full-scale security response. In the chaotic escape, Nick races through the sewer tunnels while Jack blends back into his janitor disguise and evades the incoming police.
Once at a bus station to make his getaway, Jack smugly calls Nick, only to find that Nick has anticipated his treachery. When Jack opens the carrying case, he is stunned to find it contains a mere steel rod, cleverly disguised by Nick in a move that underscores his cunning. Nick, unfazed by Jack’s threats, warns him to flee before the authorities swarm the area. As he boards a boat with the real scepter in hand, he leaves Jack to face the consequences of his betrayal.
Later, satisfied with the turn of events, Max watches a news report on the manhunt to catch Jack, who is now labeled as the prime suspect. In a final sweet moment, Nick reunites with Diane at the airport, where she greets him with a loving kiss and hug, signaling the beginning of their fresh start together.
