He was born in Modica, Sicily, in 1957. He lived in Luino from 1959 to 1977 and then in Milazzo from 1977 to 1981, where he received his degree in Literature. After his studies, he worked as a schoolteacher and began writing fiction, most of it inspired from his personal experiences and the social conditions of modern-day Sicily. His first novel, Meri per sempre, which he adapted into a screenplay for Marco Risi, is based on his experiences as a teacher in Palermo's juvenile prison. He has published a number of short stories, novels and essays since 1987. After the success of Meri per sempre, Grimaldi wrote a kind of sequel, entitled Ragazzi fuori, which was also directed by Mario Risi. Grimaldi's first film, Acla's Descent into Fioristella (1992), set in Sicily at the beginning of the 20th century, was chosen for the Venice Film Festival. With The Rebel, filmed the following year, he returned to realism and the universe of Meri per sempre, a trend which continued in The Whores (1994), based on his novel and screened at the Cannes Film Festival. Nerolio (1996) was an adaptation of Pier Paolo Pasolini's novel. An astonishing film, it established Grimaldi in the field of independent film and what is known as cinema des auteurs. He lives outside Palermo with his wife and two children.