Five thousand lies (1966)

A professor asks two poor students of law to steal, for a fee, a rare figurine from the house of a collector. After the successful outcome of the theft, the professor dies from joy, and the two students decide to return the figurine to its owner. There they meet his daughters, to whom they tell numerous lies. In the end, it is revealed that the whole thing was part of a wager between the professor and the collector, and the two students fall in love with the latter's daughters.