In the early 1960s, he found himself owing a considerable amount in back taxes. His friend Robert Kanters, who then managed “Crime-club” collection at Denoël, offered Rossi a sizeable advance to write a crime novel. Not sure of the outcome, the writer chose the pseudonym ‘Sébastien Japrisot’ which was an anagram of his real name. Within a short period of time, he wrote two crime novels: "The Sleeping Car Murders" and "Trap for Cinderella". The latter was awarded the Grand Prix de Littérature Policière in 1963. In 1965, both books were adapted into films, directed by Costa-Gavras and André Cayatte respectively.