His debut novel was The Imperfectionists (2010), about a group of journalists working in Rome during the collapse of the traditional news media.

The book became a global bestseller, published in 25 languages,[2] and Brad Pitt's production company, Plan B, optioned the film rights.

Later, in his 40s, upon realizing that he didn't want to continue writing fiction, Rachman enrolled in a master's program in behavioral science at the London School of Economics.

He moved to Paris to write fiction, and worked there at the global edition of The New York Times, the International Herald Tribune.

[8] Rachman ghost-wrote the nonfiction book, We Are Bellingcat, with Eliot Higgins, founder of the online-investigative collective known for exposing Russian-state criminality, such as the Skripal poisoning.