Woyzeck is the tragic tale of a military barber named Woyzeck, who stabs to death his beloved common-law wife, Marie, for her infidelity. We first encounter Woyzeck with his friend, Andres, in an open field outside the town. Woyzeck is having violent, apocalyptic visions and thinks that he hears voices, while Andres sees and hears nothing unusual. Next, we meet Marie. She is sitting with her child by the window, watching the military marching band go by and admiring the Drum-Major. Woyzeck arrives to give Marie money and tells her about his latest hallucinations. The next day, Woyzeck and Marie visit a fair where they are drawn into a Showman's booth. The Drum-Major spies Marie and is attracted to her instantly. He and the Sergeant follow Marie and Woyzeck into the booth, where the Showman conducts a spectacle with a dancing monkey and an "astronomical horse," all the while making jokes at mankind's expense. The Sergeant helps Marie into the front row for a better view.
Some days later, Marie sits with her child on her lap, admiring a pair of gold earrings that the Drum-Major gave her. When Woyzeck arrives, she lies and says that she found them. After he leaves, she scolds herself for being a "no-good tart," but then decides that she is no more immoral than anyone else. Our focus switches to Woyzeck, who is shaving the Officer. The latter mocks him egotistically, telling him he has no morals or virtue. Woyzeck defends himself by saying that he would be moral and virtuous if he were not so poor. Meanwhile, Marie and the Drum-Major meet in secret. The sexual tension between them is explosive and it is implied that they gratify their sexual urges. At the Doctor's office, the Doctor scolds Woyzeck for urinating in the street, since he could have used the urine for experimental tests. He is studying the effects of a peas-only diet on Woyzeck's physical and mental health. The Doctor is delighted by Woyzeck's descriptions of his increasingly tormented hallucinations, and gives him a monetary bonus.
Presumably some days later, we find the Officer visiting the Doctor. The two men exchange playful jabs before Woyzeck arrives. The Officer tells Woyzeck of Marie and the Drum-Major's affair. Woyzeck confronts Marie, who becomes defensive and dodges his accusations. In the next scene, we find the Doctor presenting Woyzeck to his students as an experimental subject. He refers to Woyzeck in the manner one might refer to a lab rat or guinea pig. Back in the guardroom, Woyzeck begins to feel very hot and tries to share his increasing mental torment with Andres, who calls him a "bloody fool." When Woyzeck joins the other soldiers at the inn, he sees Marie and the Drum-Major dancing and becomes enraged. We next find him alone in an open field. He hears voices mimicking the rhythm of the dance that tell him to stab Marie to death. That night, the voices keep Woyzeck awake.
The next day in the barrack square, Andres recounts the Drum-Major's chauvinistic comments about Marie, and Woyzeck hurries off to the inn. There, he whistles insubordinately at the Drum-Major, who beats him up and leaves him bleeding. In the next scene, he buys a knife from a Jew, who jokes that he is buying himself an "economical death." Our attention then turns to Marie at home, flipping frantically through the Bible. Her guilt has caught up with her, and she wishes to be absolved of her sin like the adultress who was brought before Christ. Woyzeck has not been by to see her in two days. While Marie flips through the Bible, Woyzeck is at the barracks, rifling through his belongings. He reads from an official military document that states his birthday as the date of the Feast of the Annunciation.
In the next scene, Marie sits with Grandmother and a group of girls on the steps to her house. When they run out of songs, the Grandmother tells a 'black fairy tale' about an orphan boy who found life empty and was miserable and lonely for all eternity. Just as she finishes her story, Woyzeck arrives and leads Marie outside the town. When she tries to get away, he accuses and insults her, and then stabs her repeatedly before the sounds of townspeople approaching scare him away. Woyzeck goes to the inn, where he jeers at a dancing woman named Kathe. She ignores him until she notices the blood on his hands and causes a scene. Woyzeck's excuses as to how the blood got on his hands do not add up, and he is forced to flee to the crime scene in search of the knife. When he stumbles upon Marie's body, he coos to her, proud that he has absolved her of her "black" deed and made her "white" and pure again. He throws the knife in a pond and then, deciding it is not deep enough, wades in after it to throw it deeper.
After he washes the blood off his hands, Woyzeck returns to Marie's house to find his child in the care of the Idiot, Karl. When he tries to embrace his child, the latter screams and pushes him away. Woyzeck sends the Idiot and child away. In the play's last scene, a Policeman addresses various townspeople including the Doctor and a Judge. He says simply: "A good murder, a proper murder, a lovely murder, as lovely a murder as anyone could wish, we've not had a murder like this for years."