Fantozzi contro tutti

Fantozzi's colleague Filini arranges for the entire office to go on a mountain trip to South Tyrol. Once in the mountain town of St. Ulrich, they realize there are no ski runs available, having they arrived in May. To keep a promise made to his wife, Fantozzi checks into a weight loss clinic run by Professor Birkermaier, a sadistic German nutritionist whose inhumane methods include fasting and corporal punishment. Birkermaier has Fantozzi watch him have dinner, but Fantozzi eventually gives in to Birkermaier's teasing and stuffs himself with the food on the table, uncaring of the punishment that awaits him.

Fantozzi's wife Pina reveals to her husband that she has fallen in love with a mysterious other man. After investigating the house and tailing Pina, Fantozzi finds out her secret lover is a young Southern Italian man who often acts in vulgar mannerisms, who works at the local bakery. Fantozzi confronts the young baker (who comically refers to him as "Fantozzo"), who instead admits that he never had any interest in Pina, and is in fact disgusted by both Pina and Mariangela's ugliness. Fantozzi returns home to find that Pina has decided to stay with him, having eavesdropped on the conversation between him and the baker.

Back at work, as a result of prayers and even Holy Masses by the employees of Megaditta, the 106-year-old Heir Director dies from rubella, much to the joy of all employees. At the director's funeral, his successor is announced to be the fearsome Viscount Cobram, a cycling enthusiast who compels all the employees to take lengthy bike rides each day. Cobram organizes a long-distance bicycle race for the entire staff to compete in. Due to the extremely unfavorable conditions of the track and the employees' general clumsiness and poor physical shape, most of the contenders do not make it to the finish line. However Fantozzi, who is doped on a mysterious drug, manages to win the race but inadvertently throws himself into a hearse that had been prepared for the event.

Then Fantozzi and Filini are invited by another manager to take a trip on his luxury yacht. However, the two accountants do not know that the man is very bad and makes them slave away as cabin boys. During the segment, the two also continuously annoy and physically damage (obviously by accident) an Englishman owning a nearby sail boat, trying to rely on Filini's (very poor) knowledge of English to communicate their apologies to him.

After an exhausting office meeting, a disgruntled Fantozzi formulates and offensive remark against the Mega-president, wishing for everyone to see it written in the sky, but unexpectedly the phrase actually appears in the sky in his own handwriting. All the employees are screened for graphoanalysis until Fantozzi is found to be the author of the slur. The Mega-president himself appears in archangel attire and forgives Fantozzi, but not before humiliating him by having the name on the writing replaced with Fantozzi's for everyone to see.