Terry Malloy, a former prizefighter, works as a longshoreman on the docks of Hoboken, New Jersey, ruled by the corrupt and brutal mob boss Johnny Friendly. Terry's brother Charley is Friendly’s right-hand man, which complicates Terry's loyalty to the gang. After witnessing the murder of a fellow worker who was planning to testify against the mob, Terry grapples with his conscience and his role in the violence that dominates the docks. Edie Doyle, the murdered worker's sister, urges Terry to pursue justice, which makes him reevaluate his life choices and the company he keeps.

Meanwhile, Father Barry, a local priest, becomes a staunch advocate for the exploited dockworkers and encourages them to stand up against the corruption that controls their lives. As Terry becomes increasingly close to Edie and influenced by Father Barry's moral guidance, he faces mounting pressure from Friendly's gang to remain silent. Torn between loyalty to his brother and the desire to do what is right, Terry must decide whether to protect himself by conforming to the corrupt surroundings or to risk everything by taking a stand against the violence and corruption that plague the waterfront.