According to Tarantino, the novel is "a complete rethinking of the entire story" and adds details to various sequences and characters, including multiple chapters dedicated to the backstory of Cliff Booth.

[2] The film's finale occurs towards the beginning of the novel, and its aftermath includes Rick Dalton earning newfound fame as a regular on The Tonight Show Starring Johnny Carson.

[7] The final part of the novel involves a phone call between Rick Dalton and Trudi Frazer on the evening after their day shooting Lancer together.

They do a line reading and reminisce about the day and Trudi reminds Dalton how lucky they are to do what they do, making him genuinely realize "for the first time in ten years... how fortunate he is and was.

[11] The deluxe edition contains Once Upon a Time in Hollywood memorabilia, including a script for an episode of Rick Dalton's Bounty Law, entitled Incident at Inez written by Tarantino.

"[3] Peter Bradshaw of The Guardian wrote: "Tarantino made a career alchemising movie trash into gold [...] Now he's done the same with ... the pulpiest of pulp fiction.

"[4] Charles Arrowsmith of The Washington Post praised the novel's "authentically pulpy atmosphere" and Tarantino's "explosive dialogue" as being "almost as effective written down as read aloud.

"[18] Katie Rosseinsky of the Evening Standard wrote: "It's hard to escape the feeling that Tarantino is writing his own fanfiction – albeit with undeniable flair.