Before the rise of on-demand entertainment sources, fans who fell in love with movies didn’t have many options beyond waiting for a theatrical re-release or home video rental. Revisiting Star Wars or King Kong instead meant picking up a novelization, a book-length prose adaptation that often expanded or added to a film’s plot.

Working from early drafts of a script sometimes meant that the writers assigned to these projects referenced details that weren’t present in the finished film. These facts can range from minor (Indiana Jones’s crushing student in Raiders of the Lost Ark may have been more of a stalker) to major (the Gremlins novelization depicts Mogwais as aliens from another planet). Check out seven of the more intriguing reveals found in the paperback versions of classic films.

1. E.T. HAD THE HOTS FOR ELLIOTT’S MOM

Steven Spielberg had enjoyed William Kotzwinkle’s 1974 novel The Fan Man so much that he invited Kotzwinkle to take on a plum assignment: novelizing the director’s big 1982 release, E.T.: The Extra-Terrestrial. Although Kotzwinkle stuck to the film’s fish-out-of-water clothesline and the friendship between the titular alien and human friend Elliott, he took some time to delve deeper into the accordion-necked creature’s proclivities—specifically, the idea that E.T. was not quite the asexual being portrayed in the film.

In the novel, E.T. is depicted as having a crush on Mary, Elliott’s (single) mother. After musing that it was unfortunate Mary was showing signs of being lonely, E.T.

"…crept down the hall to Mary's room and peeked in. The willow-creature was asleep, and he watched her for a long time. She was a goddess, the most beautiful thing he'd ever seen. … Mary, said his old heart. Then upon paddle feet, he tiptoed over to her bed and gazed more closely.”

Perhaps watching someone while they sleep is considered acceptable on E.T.’s home planet. In any event, neither the prose version of Mary nor her onscreen incarnation (played by Dee Wallace) acknowledged that E.T. wanted to swipe right.

2. RENÉ BELLOQ AND INDIANA JONES WERE COLLEGE RIVALS.

Lucasfilm Ltd.

In the opening sequence of 1981’s Raiders of the Lost Ark, we learn that two-fisted archaeologist Indiana Jones (Harrison Ford) will go to considerable lengths to acquire rare and valuable artifacts. We also discover that his archrival, René Belloq, will go a step further in seizing them. Belloq meets a satisfying, face-melting end during the movie’s climax, but viewers never learn that he and Indy had problems going back to graduate school. In Campbell Black’s novelization, it’s revealed that the two were classmates who drifted apart when Belloq plagiarized one of Indy’s essays. (The book also mentions that Indy’s love interest, Marion Ravenwood, was only 15 when Professor Jones seduced her, a fact best left on the cutting room floor.)

3. THE XEROMORPHS MIGHT BE PRETTY SMART.

In Alan Dean Foster’s novelization of 1979’s Alien, Ripley (Sigourney Weaver) is shown to be at odds with android Ash (Ian Holm) for his duplicitous behavior. Conversing with his decapitated head, Ripley discovers that Ash knows more about the Xenomorph terrorizing the crew of the Nostromo than he had let on. Near death, Ash hints that the alien might be intelligent and that she should try to communicate with it.

“Did you?” she asks.

“Please let my grave hold some secrets,” Ash replies.

Onscreen, the creature seemed less interested in interacting with humans and more preoccupied with treating them like incubators. In fairness, signs of intelligent life were hard to come by in that universe following 1986's Aliens.

4. ROCKY FORFEITED HIS WORLD TITLE TO FIGHT IVAN DRAGO.

MGM Home Entertainment

After watching his friend Apollo Creed get pummeled to death without doing anything to stop it, a penitent Rocky Balboa (Sylvester Stallone) travels to Russia to get revenge in 1985’s Rocky IV. The film makes it clear that Balboa’s bout with steroided Soviet hulk Ivan Drago is personal: He declares he’s not being paid for the match and will do it over the Christmas holiday, leaving his skittish wife and son to wonder if Rocky will be cognitively functional in time for eggnog.

The accompanying novelization, which is credited to Sylvester Stallone but may have been written by a ghostwriter, elaborates on Rocky’s obsession with the bout. After Creed’s death, Rocky tries to petition the sanctioning body for boxing to permit him to fight Drago. They refuse, and Rocky is forced to give up his heavyweight belt in order to compete. There are other complications—black sheep brother-in-law Paulie wrecks Rocky’s car—but most of it seems to be in the service of inserting details in place of the film’s trademark montages.

The book does correct one of the movie’s subjective flaws: Rocky is quick to throw in the towel during Creed’s beating, making Drago less an accidental murderer and more of an actual one.

5. GREMLINS ARE SPACE ALIENS THAT SPEAK ENGLISH.

The canon established by Chris Columbus’s script for 1984’s Gremlins says only that the Mogwai are a race of adorably over-fuzzed creatures that spawn demonic offspring when they get wet or are fed after midnight. In George Gipe’s novelization, readers learn that Mogwai are actually an alien race dispatched to different planets in order to display a “peaceful spirit.” Gipe also had the notion to have Gizmo and Stripe converse in the Queen’s English, with Stripe calling his rival “my dear enemy.” Joe Dante, the movie’s director, said Gipe “made up” their galactic backstory, telling Empire in 2014 that Mogwai are the result of dragons and pandas mating. It's as good an explanation as any.

6. JANINE DESIGNED THE GHOSTBUSTERS LOGO.

Columbia Pictures

Released in 1984, Ghostbusters succeeded where many movies subsequently failed, mixing comedy with special effects in a story about four guys who treat ghost entrapment like pest extermination. Their secretary, Janine (Annie Potts) seems unaffected by the whole enterprise, answering the phone with “Gahhstbustahs.” But in the novelization by Richard Mueller, it’s revealed that she was responsible for the most iconic image of the business: the crossed-out Ghostbusters logo.

7. FERRIS BUELLER FUNDED HIS DAY OFF WITH SAVINGS BONDS.

Novelizing a John Hughes screenplay must have seemed like a thankless task. The prolific writer/director had a very distinctive voice that was carried by his adolescent characters. One of his most enduring creations was the title teenager of 1986’s Ferris Bueller’s Day Off, an episodic tale of a high schooler (Matthew Broderick) who decides to skip class to hang out with his friends.

The film never specifies how Bueller comes up with the cash he spends in the course of his truancy, but the novel by Todd Strasser fills in the gaps. Apparently, Bueller convinces his father to give him the location of his savings bonds, which he proceeds to cash in at a local bank. He also steals a few bucks from his sister Jeanie.

The book provides other details, like what Ferris and his friends ate at the French restaurant and the fact that Ferris is apparently friendly with Garth Volbeck, the juvenile delinquent played by Charlie Sheen that Jeanie runs into in the police station near the end of the film.