A man dressed in a zoot suit uses a switchblade to cut through a backdrop of a newspaper’s frontpage, which reads, “ZOOT-SUITER HORDES INVADE LOS ANGELES.” Emerging from the hole he cut, El Pachuco adjusts his outfit and combs his hair, eventually addressing the audience by asking them in Spanish slang if they’re looking at his clothes. Switching to English, he explains that the audience is about to see a play about the Pachuco way of life, saying that the archetypical Pachuco is first and foremost a performer, somebody who takes part in constructing what it means to be Chicano. The 38th Street Gang then enters and erupts into an animated party.
Wearing a zoot suit, Henry Reyna, leader of the 38th Street Gang, greets his friends. The gang has a good time they spot members of the Downey Gang—their rivals. A fight almost erupts, but El Pachuco stops it. Still, the party is interrupted by a siren, and Sargent Smith and Lieutenant Edwards burst onto the scene, telling the dancers to put their hands up. Smith calmly tells a white sailor at the party to leave, but then he and Edwards arrest the 38th Street Gang before bring them to jail. Members of the press arrive and shout out headlines: the 38th Street Gang has been arrested on suspicion of the recent murder of José Williams at Sleepy Lagoon.
In jail, Henry speaks to El Pachuco, the narrator who also functions as a part of Henry’s conscience. El Pachuco says the city is “cracking down on pachucos.” This disheartens Henry, who complains that the police have repeatedly pinned crimes on him even though he’s innocent—and this time it’s worse because he’s supposed to report to the Navy the following day to fight in World War II. El Pachuco doesn’t understand why Henry wants to do this, pointing out that the United States doesn’t care about him. He tells Henry to forget about foreign wars because he has his own war to fight at home.
A member of the press enters with Edwards and Smith, reading a headline aloud that reveals the police have arrested 22 members of the 38th Street Gang. Approaching Henry, Edwards and Smith talk to him about their suspicions, saying they’ve been told to round up “malcontents,” especially since the country is at war. Edwards uses this as an excuse when Henry reminds him that Edwards has arrested him on false charges before, and goes on to say that he will let Henry out of jail and allow him to join the Navy if he provides a statement about what happened to José Williams. With El Pachuco giving Henry advice that only he can hear, though, Henry refuses to talk.
When Edwards and Smith leave, Henry thinks back to the night of the Sleep Lagoon murder. He’s back at this house, getting ready to go out dancing with his new girlfriend, Della, his sister Lupe, and his younger brother, Rudy. As they prepare to leave, Henry’s parents, Dolores and Enrique, take issue with the way Lupe’s short skirt and Rudy’s zoot suit. On their way out, Enrique tells Henry not to let Rudy drink beer.
Back in the present, press members question Edwards about the murder trial and the “Mexican Crime wave.” In response, Edwards gives scant details about the crime scene, explaining that the Sleepy Lagoon is a reservoir where young Chicanos often swim. Hearing this, a reporter named Alice asks if this is because Chicanos aren’t allowed at the public pools, but the other journalist react negatively to this question.
In jail, Henry talks to his friends Joey, Smiley, and Tommy about the way the press has portrayed them. A white lawyer named George then enters and introduces himself, explaining that Henry’s parents hired him to represent the gang in court. Despite the men’s initial skepticism, George makes it clear that he isn’t expecting to make money from representing them. He also emphasizes just how badly the members of the 38th Street Gang need a lawyer, since biased news coverage has already swayed popular opinion against them. In response to this, George explains, a committee has formed in the gang’s support, demonstrating that there are people who care about giving them the justice they deserve. Reluctantly, Henry and his friends accept George’s offer.
The narrative jumps back to the night of the murder. At a party with Henry and the rest of the 38th Street Gang, Rudy gets drunk. This becomes a problem when members of the Downey Gang, led by a man named Rafas, pick a fight with Rudy. Henry steps in just before things escalate. He and Rafas have a knife fight, which Henry wins by knocking Rafas down and stabbing him in the neck. Just then, El Pachuco interrupts by snapping his fingers—everybody freezes in place. He tells Henry that the play doesn’t need any more bloodshed, especially between two Mexicans. When Henry points out that he must kill Rafas to avoid getting killed himself, El Pachuco says that this kind of violence is exactly what the audience paid to see—a point that convinces Henry to let Rafas go.
The narrative returns to the jail, where George visits Henry and introduces him to Alice, a reporter working to clear his name. Wanting to write an unbiased story, she asks Henry questions about the night of the murder, but he doesn’t see the point in talking. Alice points out that other newspapers are actively spreading rumors about the gang to ruin their public image. She also says that the entire concept of Los Angeles’s so-called “Mexican Crime Wave” was invented by a newspaper owner who just wants to make money. For this reason, she says, it’s important that the people hear Henry’s side of the story. When Henry remains skeptical, she tells him that she grew up in Los Angeles but never heard about the Chicano population. Now, though, she’s eager to learn about the community, a fact that makes Henry a bit more receptive to what she says.
During the 38th Street Gang’s trial, George tells the judge that the jail hasn’t given Henry and his friends clean clothes or fresh haircuts like they normally do before sending prisoners to court. However, the public prosecutor claims that this is because the gang members are identifiable to witnesses by their appearances, and rules that they won’t be allowed to change how they look. He also says that each member of the gang must stand whenever the prosecutor mentions him, claiming that the witnesses need them to do this in order tell them apart. George objects, saying that this might affect the way the jury rules, since Henry and his friends will risk incriminating themselves if they stand during allegations of criminality. Again, though, the judge overrules this objection.
As the trial proceeds, Della takes the stand and describes what happened on the night of José Williams’s murder: she and Henry were at the Lagoon having a romantic evening—Henry even suggested they get married when he returns from the Navy. As they looked out over the lagoon, they were curious about a nearby party but then noticed the Downey Gang vandalizing Henry’s car. Henry tried to fight them, but they beat him unconscious. When he came to, Henry went to get the rest of the 38th Street Gang, returning to the lagoon to find that the Downey Gang was no longer there. Just before they were about to leave, though, they heard noise from the nearby party and went to see what was going on—apparently, the Downey Gang had just stirred up trouble at this party, so the partiers attacked the 38th Street Gang when they saw them approaching, thinking they were the Downey Gang returning for more trouble. In the chaotic fight that ensued, José was beaten to death, but the 38th Street Gang was unaware of this at the time.
After Della finishes her account, the prosecutor and judge attempt to frame Henry and his friends as criminals and murderers. Finally, in his closing statement, the prosecutor suggests to the jury that letting these young men free would be dangerous to American society. George counters this argument in his own closing statement, insisting that Henry and his friends are innocent Americans and that to convict them of murder without sufficient evidence would be to undermine the country’s core values of justice. Despite this, the jury sentences the members of the 38th Street Gang to life in prison.
In the coming weeks, Alice writes letters to Henry and his friends while working hard to publish an article about their case, since George has appealed the court’s decision. During this time, Henry becomes fond of Alice, and they develop a vaguely romantic relationship. However, they find themselves at odds when Henry says he wants to drop out of the appeal. Incredulous, Alice tells him he can’t do this, pointing out how hard she’s worked to help him. Henry tells her to keep her self-righteous altruism to herself, reminding her that he never asked for help. As this argument continues, Alice becomes upset and finally breaks down, lamenting the fact that—no matter how hard she works—nobody takes her seriously, discounting her as too “sentimental” and too untrustworthy because she’s a Jewish communist. Hearing this, Henry remarks that she finally sounds like she really means what she’s saying, and he recommits himself to the appeal.
Shortly after this interaction, Henry is thrown into solitary confinement for fighting with a guard. While he’s in isolation, the Zoot Suit Riots break out over Los Angeles, and Rudy gets swept up in the violence when white servicemen target him and other young Chicano men for wearing zoot suits. Though this devastates the Chicano community, some good news follows on the heels of the riots: Henry and the rest of the gang win their appeal and are released. When they come home, they have a large party at Dolores and Enrique’s house, but this is not the happy, simple ending it might seem. Rather, Henry has to decide whom he loves more: Della or Alice (he never makes a definitive choice). Meanwhile, Rudy warns Henry against wearing his zoot suit. Rudy himself joined the Navy while Henry was in prison and will be returning to the war the following day. As Della and Alice wait for Henry to decide between them, a police officer arrives outside and tries to arrest Joey, but Enrique doesn’t let Henry outside to help, not wanting his son to get wrongfully arrested once again. Instead, George, Alice, and Tommy handle the matter, and then the entire cast of characters takes turns narrating the rest of Henry’s life. A member of the press enters and says that Henry goes back to prison in 1947 for robbery and assault and then kills an inmate before eventually dying in 1955. El Pachuco, however, says that this is just the story the press sets forth, at which point Rudy claims that Henry goes to Korea and dies in action in 1952, receiving a Congressional Medal of Honor after his death. Alice, for her part, says that Henry marries Della, with whom he has five children. As everyone calls Henry different names (“the born leader”, “the social victim,” etc.), El Pachuco sums up Henry’s life by saying, “Henry Reyna…El Pachuco…The Man…the myth…still lives.”
