Marcus Fisher, a tagger and member of the "A" Street Deuces, is with his friends as another painter comes over and starts painting over Marcus' wall in an alleyway. The other gangers, lead by String, give Marcus a gun and tell him to take care of it. Marcus goes over to confront the man, Henry Santos, but Santos doesn't believe that Marcus will shoot him over it. He tries to take the gun away and Marcus accidentally pulls the trigger. Marcus runs for the car and the Deuces drive back to their garage where they congratulate Marcus on becoming a man.
Later that night, Marcus goes to the site after the police have taken Santos' corpse away. He looks up at the wall and sees that his painting has changed: now Santos' dead body, shot in the chest, is part of the image. The next morning, Marcus goes back and paints over it but the police grab him as he leaves. Rosas, a local gang counselor, vouches for Marcus and gets the police to release him. He knows Marcus and warns him that the police are looking for the person who killed Santos. Rosas tries to get Marcus to quit the Deuces but Marcus refuses and leaves. He can't get the image of the painting with Santos' corpse out of his head, despite his girlfriend Shauna's reassurances that there's nothing he can do about it.
That night, Marcus meets with the Deuces and their girlfriends and young admirers. They all congratulate him on finally becoming one of the gang and he gets a Deuces tattoo on his right arm. Rosas shows up and wants to show Marcus something. As they drive through the city, Rosas talks about how Santos was a new artist with good reviews and his entire life ahead of him. They arrive at the alleyway and Rosas shows Marcus the wall. Now a white silhouette has appeared over Santos' corpse, holding a gun… and it has a Deuces tattoo.
Marcus goes back later and paints over the entire wall with white paint. He sits down to watch and dozes off for a second, then looks up to discover that the images are emerging out of the still-wet paint. Worse, the image of the shooter is now dressed exactly like Marcus: the only thing still blank is the face.
The other Deuces have seen Marcus with Rosas and think he's going to snitch to the cops. Shauna, String's cousin, tries to warn Marcus but he's increasingly eaten up with guilt over the murder. Rosas finds Marcus on the streets and informs him that the coroner's report indicates that Santos had powder burns on his right arm, like he didn't believe the person who shot him was going to really do it. Rosas figures that Marcus killed Santos but that it was an accident. He warns that the Deuces own Marcus now and they want to drag him down because he has the chance to make something of himself as an artist and they've got nothing.
Marcus goes to String and the others and says he came to them because he has nothing to worry and doesn't plan on confessing. They're skeptical but Shauna comes in and tells them they need to look at the wall. They go there and discover that now the image of the shooter is complete: it's Marcus. The Shauna and the gang are convinced Marcus is boasting about the murder and congratulate him, then leave. Marcus grabs a sledgehammer and smashes his image and Santos' off of the wall, then collapses in shock.
The next morning, Marcus wakes up and sees that the images are still gone. However, he feels a pain in his chest and rips open his shirt to see the images are branded on his chest. He runs out onto the street and finds Rosas and the police, and confesses to the accidental shooting. He shows them his chest… but there's nothing there now. Rosas notes that he knew Marcus wasn't a killer, and takes Marcus away.