Count Almaviva, disguised as a soldier and pretending to be drunk, enters the house and demands to be quartered there. In fear of the drunken man, Berta the housekeeper rushes to Bartolo for protection. Bartolo tells the "soldier" that he (Bartolo) has an official exemption which excuses him from the requirement to quarter soldiers in his home. Almaviva pretends to be too drunk and belligerent to understand, and dares Bartolo to brawl. While Bartolo searches his cluttered desk for the official document which would prove his exemption, Almaviva whispers to Rosina that he is Lindoro in disguise, and passes a love-letter to her. Bartolo suspiciously demands to know what is in the piece of paper in Rosina's hands, but she fools him by handing over her laundry list. Bartolo and the Count argue loudly. Basilio enters; then Figaro, who warns that the noise of the argument is rousing the whole neighborhood. Finally, the noise attracts the attention of the Officer of the Watch and his troops, who crowd into the room. Bartolo demands that the Officer arrest the "drunken soldier". The Officer starts to do so, but Almaviva quietly reveals his true identity to the Officer, and he (the Officer) backs off. Bartolo and Basilio are astonished and mystified; Figaro laughs quietly at them. (Finale: "Fredda ed immobile, come una statua"; "Cold and still, just like a statue"). The confusion intensifies and causes everyone to suffer headaches and auditory hallucinations ("Mi par d'esser con la testa in un'orrida fucina; dell'incudini sonore l'importuno strepitar"; "My head seems to be in a fiery forge: the sound of the anvils deafens the ear").