The next morning, the servant Sosias announces Thebes' victory over Athens and the return of the Theban army. He sees a double of himself, who is actually Mercury, who acted as guard the night prior. Confusion follows.
The next day, the attendant Sosias declares Thebes' victory over Athens and the return of the Theban army. He meets a double of himself, which is actually Mercury, who served as guardian the previous evening. This results in confusion.