Verona Beach is a gritty, run-down city bisected by two major organized crime families, the Capulets and the Montagues, who also happen to be bitter, deadly rivals. The hate between the two families runs far and deep, so much so that even the current clan patriarchs no longer know why they hate each other so much. Though the origin of the feud is lost, the enmity is strong and it profoundly affects the younger members of the clan.
While refueling their car, a group of Montague boys, led by Benvolio, Romeo’s cousin, are chanced upon by a group of Capulet boys, led by Juliet’s cousin, Tybalt, and are goaded into a drawn-out gunfight. The ensuing battle results in massive property damage, given that they were shooting at each other in a gasoline station. The Chief of Police breaks up the fight, culminating in the arrest of both parties; during their arraignment Capt. Prince warns each of the clan patriarchs that he will not tolerate any further disturbances, with the barely veiled threat that their lives “shall pay the forfeit of the peace” in the event of another skirmish.
Benvolio heads to the beach to meet up with Romeo whom he finds brooding over Rosaline, a woman he is smitten with. Together, they decide to pass the time playing pool. While engaging in a bit of banter they learn of a huge costume party to be held at the Capulet mansion that evening. They all decide that it would be great fun to crash the party. Initially, Romeo declines to join them, but when he discovers that Rosaline is attending he decides to tag along. En route to the Capulet bash they meet up with their common friend, the peerless party animal, Mercutio, who has scored their tickets to the party of the year—along with some designer drugs. Mercutio gives Romeo a tablet of ecstasy, and he is soon overcome by the drug, retreating to the bathroom to try to revive his senses. While trying to shake off the effects of the drug he sees Juliet through an aquarium he is admiring. Their gazes meet and they instantly fall deeply in love. Tybalt, however, spots Romeo, and recognizes him as a member of the Montague clan and vows to kill him for invading their family’s home. The Capulet clan head, Fulgencio, stops Tybalt, warning him not to make a scandal in the sight of his guests.
Romeo and Juliet sneak into an elevator amidst the crowds and passionately kiss. Juliet’s nurse finds the lovers and tears Juliet away, divulging the bitter truth: Romeo is a Montague—scion of her clan’s most hated enemy. Mercutio in turn drags Romeo away, stating that the fun is over and it's time to seek mischief elsewhere. But Romeo is fully taken by Juliet, and he sneaks back into the mansion and hides beneath her balcony. Juliet comes out to meet Romeo and confesses her love for him, warning him that he is in grave danger; but he assures her that he doesn’t care if he is caught.
Juliet conspires with Romeo, telling him that if he wants they can be married the very next day. Elated, Romeo visits his old friend, Father Laurence, an accomplished herbologist and humble priest, telling him of his plans to marry Juliet. Father Laurence consents to wed the two, hoping that their union might bring peace to the feuding clans. Romeo informs Juliet’s Nurse that all the necessary arrangements have been made and the star-crossed lovers are wed.
Tybalt has been searching for Romeo, spoiling for a fight, but instead comes upon Mercutio and the rest of the Montague boys as Romeo arrives. Tybalt, who has wanted to avenge his clan for the invasion of their party, requests to have a “talk” with Romeo. Romeo, having just married Juliet, wishes to make peace but Tybalt continues to harass him. This proves too much for Mercutio to take and a fight breaks out between the two with Mercutio gaining the upper hand. Mercutio is about to deal a fatal blow with a log when Romeo stops him, allowing Tybalt an opportunity to fatally wound Mercutio with piece of broken glass. Initially, Mercutio bravely shrugs of the injury as “a scratch” but quickly realizes that he will not survive his injuries. He pronounces a curse over both clans with the last of his strength, finally dying in Romeo’s arms.
A grief-stricken and rage-consumed Romeo pursues Tybalt with his race car, colliding with Tybalt’s vehicle and first stunning him. He then proceeds to gun him down. Capt. Prince then banishes Romeo from the city of Verona Beach for violating the ban on brawling in the city and Romeo hides out with Father Laurence while waiting for the heat to die down. Father Laurence nurses Romeo’s wounds and assures him that he will help Romeo and Juliet return to Verona and make peace with their respective family members. Juliet’s Nurse arrives and informs Romeo that his wife is waiting for him. Romeo and Juliet are reunited, and they consummate their marriage.
Still reeling from the emotional high of having consummated their secret marriage, Juliet’s happiness soon plummets as her parents breaks the news to her that they have made arrangements for her to be wed to the governor’s son and Verona's most eligible bachelor, Dave Paris. Juliet passionately refuses the plan, which causes her father to threaten to renounce her. Gloria Capulet and the Nurse intervene, trying their best to convince Juliet that it would be for the best if he agreed to her father’s wishes and marry Paris. She runs away to seek help and advice from Father Laurence. Extremely distraught, Juliet contemplates suicide as a solution, and this sparks an idea in the wily priest. Together they devise a plot that involves Juliet faking her own death through the use of an herbal tonic he has created that will simulate death but will wear off after 24 hours. Once “dead,” Juliet will be entombed in the Capulet crypt where she and Romeo will be reunited. Together, the two can travel to Mantua where they can live out the rest of their days as simple folks.
Juliet drinks the formula and promptly falls into a deathlike coma, is declared dead, and is placed in the Capulet family crypt. But things do not all go as planned, as Balthasar, one of Romeo’s kinsmen, learns of Juliet’s death and reports it immediately to him. Driven nearly insane by the grief, Romeo rushes back to Verona, missing the messenger sent by Father Laurence to report that Juliet is not dead ,but merely in a coma. Upon reaching Verona, Romeo purchases poison from an apothecary in the seedier part of the city. Capt. Prince is alerted that Romeo is back and tries, unsuccessfully, to capture him. Father Laurence discovers that Romeo is unaware of their plans but he is too late to stop the impulsive young lover. Romeo enters the church where Juliet’s wake is being held.
He bids her farewell and downs the fast acting poison only to see Juliet awakening from her chemically induced coma, tragically seeing each other for the last time. A distraught Juliet then picks up Romeo’s gun and shoots herself in the temples, ensuring her immediate death. The pair is found dead in each other’s arms. The city coroners immediately place their remains inside body bags, but before closing them completely Capt. Prince displays both Romeo and Juliet’s death-pale faces to news crews and the grieving families, condemning both the Montagues and the Capulets for perpetuating their feud, stating “all are punished” for participating, even the good Captain, as he has lost good men in the process of trying to keep the peace. The coroners zip up the body bags completely, and the film ends with the TV reporter's report of the tragedy of Romeo and Juliet.