The youths have taken their place on the left of the proscenium, the young girls on the right and the old people in the centre: shouts and responses with sensuous affirmations of love between the young persons increase ecstatically in alternation with furious outbursts on the inanity of love from the bad-tempered old people.
Catullus is leaning on a pillar when Lesbia appears. They ensconce themselves and Catullus falls asleep with his head on the lap of his girlfriend who soon leaves the sleeping Catullus to dance before her aficionados in the tavern.
Act 2, Night:
Catullus is asleep on the street in front of Lesbia’s house. Lesbia appears to Catullus in a dream, but is caressing another man, Caelius. Catullus awakes from his sleep broken-hearted.
Catullus writes a love-letter to Ipsitilla who appears at the window. Ameana, an old paramour of his, makes advances to Catullus, but he rejects her and searches for Lesbia among the aficionados and paramours. Lesbia spies Catullus, but he rebuffs her and she flees broken-hearted.
The old people admit they have lost the game. The young people, unconvinced, break out anew in declarations of reciprocal passion.
 Werner Thomas in: Pipers Enzyklopädie des Musiktheaters, Vol. 4, Munich 1991, p.581 ff.