Teorema (1968)

Second Italian edition of Pier Paolo Pasolini's Teorema, published in the same year of the eponymous movie by the autor and director.

A mysterious and attractive young man arrives at the suburban home of a wealthy businessman in Milan and invites himself to stay. From the start, he exerts a quiet but powerful influence over the household. Gradually, each member of the family—the busy father, the unhappy mother, the restless daughter, the uncertain son, and the maid from the countryside—develops deep feelings for him. Then, as suddenly as he appeared, he leaves.

In his absence, the family must face the changes his presence set in motion. How will they continue without him? Is there a way out of the spiritual emptiness of modern capitalist life—toward some kind of personal or moral renewal? 

New York Review of Books characterizes it as "the most enigmatic of Pier Paolo Pasolini’s four novels. The book started as a poem and took shape both as a work of fiction and a film, also called Theorem, released the same year. In short prose chapters interspersed with stark passages of poetry, Pasolini tells a story of transfiguration and trauma."