Spacey will be seen in the role of the legendary writer, while Booth plays Jamie, a young British writer whose work catches Vidal's eye, reported Deadline.
Director Michael Hoffman is helming the project, which is being shot in Italy.
Booth's latest outing is "The Limehouse Golem" with Bill Nighy and Olivia Cooke. In October, he'll be seen in "Loving Vincent", the crime mystery surrounds the death of famed painter Vincent van Gogh in 1890 France.