The film starts in a sun-baked and seemingly empty Rome on an August morning during the Ferragosto national holiday. A young, timid law student, Roberto (Trintignant), gazing out his window, is asked by a 40-ish man named Bruno (Gassman), who is passing on the street below at the wheel of a convertible Lancia Aurelia, to make a phone call for him. Roberto tells him to come up and make the call himself. After Bruno fails to contact his friends — he is running a full hour late for his meeting with them, something he apparently doesn't deem a good enough motive for them to have "abandoned" him — he insists on repaying Roberto's courtesy with an aperitivo. Tired of studying for the day and falling prey to Bruno's enthusiasm, Roberto accepts.