Based on Leo Tolstoy's novel, Father Sergius, Night Sun stars Julian Sands as Sergio, a nobleman in 18th-century Italy who is expected to marry a duchess, Nastassja Kinski. Upon learning that she was previously the King's mistress, Sergio turns his back on society and becomes a monk. While at the hermitage he tries to resist all sexual temptations before him and soon becomes known as a miracle worker. Eventually he succumbs to a young seductress and knowing he is undeserving of the adulation, leaves the hermitage to travel around as a homeless beggar.

Paolo and Carlo are good friends. The first introverted, disillusioned and intellectual, while the other is happy if shallow. Despite their differences they share accommodation. Paolo runs an “alternative” kind of library; Carlo plays the violin in a little band. Their lives go on peacefully, when suddenly Paolo falls in love with one of his a customers - Lili, an amateur actress - whom he decides to take home. Carlo doesn’t react well to the fact he’s got to share with a third person, so he comes up with a weird idea - he flirts with the new girl and manages to seduce her. Paolo thinks his best friend is now guilty of a real betrayal, while Lili is undecided: she’s attracted by both the culture of Paolo and the physical attraction of Carlo. This love triangle ends when Paolo tries to commit suicide, Carlo feels guilty and Lili leaves them both, returning to her previous life and still hoping to find her one true love.

This coarse bedroom farce takes place at the St. Moritz ski resort over a Christmas vacation. Among the couples whose lives intersect are a widowed artist honeymooning with his second wife, a gay man traveling with his son and his lover (and hiding each from the other), a snobbish couple from Milan who have been forced to share a suite with a pair of crass Romans, etc.

Marino Pacileo has a soft spot for gambling. When he discovers that Lila's father, the young Chinese girl that he is in love with cannot pay a debt, the gambler steals money from the jail he is in to help the love of his life.

In Naples, Professor Bellavista is a retired man, passionate about the philosophy and thought of Ancient Greece. Every day, in his luxurious apartment, he teaches his lessons of life to the poor-nothing (his friends), who are dazzled by his reasoning. One day, however, the quiet life of the building of Bellavista will be disturbed by the arrival of a director of Milan. Between Naples and Milan there contrast, because the Neapolitans are accustomed to enjoy a quiet life, always based on the "philosophy of pleasure and delay", while the northern Italians are very strict and punctual.

A doorman and a street cleaner, intrigued by the passage of Halley's Comet, ask Professor Bellavista if they can observe the sky through his telescope. The two, instead of observing the comet, end up framing a window of the apartment opposite and believe they have discovered a crime. So they set out in search of the body.

Aldo Viezzi, a brilliant surgeon secretly addicted to cocaine, retreats to Prague for research but sinks deeper into dependency. With sociologist Teresa’s help he uncovers a drug-trafficking manager, endures a forced, drug-free operation to save a kidnapped patient, and finds the strength to confess his addiction and bring the trafficker to justice.