The Captain’s room.
The ordinary soldier Franz Wozzeck is shaving the Captain, as he does every day. The Captain loses no opportunity to deride the man and to accuse him of immorality for living with Marie, a former prostitute who has had a child by him. Wozzeck attempts, without success, to explain his reasons.

In the countryside.
Helped by his fellow-soldier Andres, Wozzeck is collecting firewood. But very soon the landscape around him turns into an ominous and unbearable nightmare.

Marie’s room.
Marie watches with fascination the fine bearing of the Drum Major, as he marches past her house at the head of a military band. Margret, her neighbour, makes cutting remarks about her conduct. Alone, Marie tenderly rocks her baby. When Wozzeck bursts in, suffering from hallucinations, his mistress tries to distract him by talking about their child. But he rushes out without listening.

The Doctor’s clinic.
In exchange for a modest sum, Wozzeck has offered himself as a guinea-pig for the parascientific experiments which the Doctor practises on him to reveal signs of madness. With cynical satisfaction, the Doctor observes that Wozzeck’s state of aberration mentalis partialis has become acute.

A street, outside the door of Marie’s home.
Having noticed Marie’s admiration for him, the Drum Major soon makes unambiguous advances to her until, after some brief hesitation, she succumbs.