Although he was a respected novelist and poet, Vincenzo Cerami, who has died aged 72 after a long illness, was perhaps best known as a screenwriter, thanks to his long partnership with the director Roberto Benigni. The pair co-wrote six films and had their greatest success with La Vita è Bella (Life Is Beautiful, 1997), which starred Benigni as a Jewish internee in a concentration camp, desperately pretending to his young son that it is all a game. The film won three Oscars and had a further four nominations, including for best screenplay. "Knowing Vincenzo was a gift," said Benigni, "because he taught people's hearts to beat."
On their early films together, Cerami was not able to totally sublimate Benigni's excesses as an actor. Nevertheless, Il Piccolo Diavolo (The Little Devil, 1988), Johnny Stecchino (1991) and Il Mostro (The Monster, 1994) were all big box-office successes. Only with Life Is Beautiful did Cerami succeed in writing a script that was a perfect vehicle for Benigni's extraordinary dramatic as well as comic abilities.
Cerami was born in Rome, where his Sicilian father worked at Ciampino airport. Vincenzo was a shy and sickly boy and his passion for literature was fuelled by one of his teachers, Pier Paolo Pasolini, who had yet to embark on his own career in film. Asked to write an essay on the subject "a day in the mountains", Cerami – who had never climbed a mountain – invented a colourful horror fantasy which so impressed Pasolini that he gave it full marks and read it to an applauding class. Cerami gained confidence and decided he wanted to become a writer.
In his later teens, having regained his physical strength, he played rugby and only an accident stopped him from competing at national level. He studied at a scientific institute to please his parents but renewed contact with Pasolini, who took him along as a volunteer assistant on his film Comizi d'Amore (Love Meetings, 1965), touring the country from Bologna to Palermo to interview Italians about sex. He later assisted Pasolini on Uccellacci e Uccellini (The Hawks and the Sparrows, 1966), a parable contrasting Marxist and Catholic faiths, starring the great comic actor Totò.
Now inside the cinema world, Cerami soon found work as screenwriter. While working on one film, he tried to get a part for Mimsy Farmer, a young American actor he had met while she was holidaying in Italy. Farmer did not get the part and Cerami was fired, but they married in 1970 and had a daughter, Aisha.
He had meanwhile written his first novel; Pasolini showed it to the writer Italo Calvino, who was so impressed that he found a publisher and wrote an introduction. Published in 1976 as Un Borghese Piccolo Piccolo (An Average Little Man), it was a cruel story of a civil servant whose son is accidentally killed during a robbery; the father chases down the killer and tortures him to death. The novel was filmed by Mario Monicelli in 1977 and Alberto Sordi courageously played this unsympathetic Death Wish-style character, giving his greatest performance.
Cerami's career as a respected author took off. Among his most critically acclaimed works was an ironic novel in verse called Addio Lenin (Goodbye Lenin, 1981). His screenplays, meanwhile, particularly suited over-the-top comic actors, enabling them to give strong dramatic performances. He contributed to Ettore Scola's script for Il Viaggio di Capitan Fracassa (The Voyage of Captain Fracassa, 1990), giving more depth to a character played by Massimo Troisi.
A radical leftist, Cerami wrote serious screenplays with the director Gianni Amelio, including I Ragazzi di Via Panisperna (The Boys of Via Panisperna, 1988), about a group of young scientists working with the physicist Enrico Fermi, and Porte Aperte (Open Doors, 1990), a powerful adaptation of Leonardo Sciascia's anti-mafia novel.
With the director Marco Bellocchio, Cerami collaborated on the scripts for Salto nel Vuoto (A Leap in the Dark, 1980), which starred Michel Piccoli and Anouk Aimée as siblings with an ambiguous relationship, and Gli Occhi, la Bocca (The Eyes, the Mouth, 1982), influenced too much, in Cerami's view, by Bellocchio's psychoanalyst guru, Massimo Fagioli.
After his divorce from Mimsy, Cerami married Pasolini's cousin Graziella Chiarcossi. They had a son, Matteo, who in 2010 directed his father's screenplay for Tutti al Mare (All at Sea). This was an update of one of the films Cerami wrote for the director Sergio Citti, Casotto (Beach House, 1977), which takes place inside a beach cabin.
In the 90s, Cerami wrote librettos for several theatrical works with music by Nicola Piovani, who won an Oscar for his Life Is Beautiful score. Cerami's last book of poetry, Alla Luce del Sole (In the Sunlight), was published earlier this year.
He is survived by Graziella, Matteo and Aisha.
• Vincenzo Cerami, author and screenwriter, born 2 November 1940; died 17 July 2013
