In a murky world filled with shady dealings and questionable allegiances, Eddie Coyle navigates the perilous realm of a low-level gunrunner based in Quincy, Massachusetts. His livelihood hinges on supplying firearms to a bank heist crew led by Jimmy Scalise and Artie Van, obtaining these weapons from the cunning Jackie Brown with meticulous precision. However, Coyle's life hangs by a thread as he faces looming prison time for his involvement in a truck hijacking masterminded by the sly Dillon, who runs a local tavern frequented by Coyle.
As his plight intensifies, Coyle seeks the help of ATF agent Dave Foley, hoping to negotiate a lenient sentence in exchange for information. Yet, the alliance unravels into a tangled web of betrayal, as Coyle remains unaware that Dillon has been secretly collaborating with Foley, meeting him weekly to collect a $20 welfare stipend.
Meanwhile, the audacious bank robbery crew, spearheaded by Jimmy Scalise and Artie Van, executes a daring heist at the South Shore National Bank, during which they kidnap Mr. Partridge, the bank manager. In light of these developments, Coyle meets with Foley to propose arresting Jackie Brown in exchange for a better deal, but Foley remains evasive about the proposition.
Simultaneously, Jackie finds himself embroiled in a high-stakes deal as he agrees to sell M16 rifles to a couple of hippies in Cambridge. Although initially hesitant, his desire for profit compels him to pursue the weapons from an associate in Rhode Island. The following day, urgency strikes as Coyle pressures Jackie into acquiring guns for the robbers' next venture. Overcoming his reservations, Jackie embarks on a nocturnal journey to Rhode Island to secure the needed firearms, showcasing his cleverness in navigating this dire situation.
With the crew's momentum escalating, they commit to a bold heist at a bank in South Weymouth, only to trigger a silent alarm that compels them to execute a hasty escape, culminating in the tragic murder of a teller. This catastrophic turn of events heightens their notoriety, marking them as wanted for capital murder. In the midst of this chaotic backdrop, Jackie meets Coyle in a grocery store parking lot in Dedham to finalize the gun transfer—a seemingly standard exchange that turns sinister when Coyle later alerts Foley about Jackie's earlier rendezvous with the hippie couple at the train station.
Unbeknownst to Jackie, Foley and his surveillance team have laid in wait, ready with sniper rifles. When the couple arrives, Jackie, sensing something amiss, instructs them to meet him later, but it's too late. Foley and his agents pounce, arresting Jackie and revealing Coyle's betrayal, as he was merely a pawn in Coyle's plan to safeguard his own interests.
The repercussions of this betrayal reverberate when Foley reveals to Coyle that Jackie's arrest paves the way for his deal. In preparation for their next heist, the crew attempts to kidnap the bank manager but falls into an ambush set by Foley and his team, leading to their subsequent arrest.
The following day, Coyle is blindsided by Foley's visit, presenting him with a newspaper article detailing the arrests of Scalise and his crew. This shocking news leaves Coyle grappling with feelings of betrayal and hopelessness, only to then receive an unexpected invitation from Dillon to attend a Boston Bruins game at the renowned Boston Garden.
The evening unfolds with a surprising sense of calm as Coyle drinks to excess and ultimately passes out during the car ride home. However, his "wife's nephew," a cunning accomplice, drives them to a remote location where Dillon unexpectedly deals a fatal blow to Coyle. They discard their vehicles at a nearby bowling alley, vanishing into the night.
As dawn breaks over Boston City Hall's stately silhouette, Dillon and Foley converge outside its grand entrance, tension hanging heavy in the air. Foley expresses his gratitude for Dillon’s assistance in delivering Scalise and his crew, while an undercurrent of menace lingers as Foley hints at being aware of Dillon's possible involvement in Coyle’s demise. Ultimately, the two men part ways, each disappearing into the city’s hustle and bustle, their fates as entwined and complicated as the narrative of deceit and survival that has unfolded.
