Michael Crichton’s original novel Jurassic Park was a swift bestseller upon its release in 1990 and widely regarded as one of the author’s better works. His ability to turn intriguing scientific theories into interesting narratives found no better form than the notion of a large corporation successfully cloning dinosaurs with the intention of putting them on display in a zoo. It carried weighty notions in easy-to-digest form -- providing a shorthanded sketch for things like chaos theory -- along with a colorful narrative that let people enjoy an adventure story without getting too deep into the conceptual underpinnings.

Even so, changes were made in adapting it to the big screen. Director Steven Spielberg and screenwriter David Koepp had to present the same story to a much wider audience, which meant systemic changes in the characters and structure. Along with Ian Malcolm -- who went from a smug plot expositionist to a strangely enduring audience surrogate -- the biggest character shift came with John Hammond, the billionaire industrialist who creates the park and its dinosaur exhibits. The movie depicted him as a well-meaning philanthropist who let his vision blind him to the park’s dangers. In the book, however, he was worse. Much worse.

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John Hammond Is the Villain of Michael Crichton's Jurassic Park Book

John Hammond holding the amber cane and smiling at his creation.

According to supplemental material on the Blu-ray of the first Jurassic Park, Crichton’s first idea for the novel involved a graduate student who created a dinosaur. Upon further development, he reasoned that there would be no practical reason to do so, given the presumed expense of researching and recreating prehistoric genetics. Only a large corporation would have the necessary resources, and the only reason they might embark upon it would be to make money. Hence, the core of the story was born.

Hammond became the face of all of that: the founder and CEO of InGen Corporation, who created the park on Isla Nublar and its inhabitants. From a purely narrative perspective, there isn’t much difference between his role in the novel and the one in the movie. With investors growing nervous, he brings in a set of outside consultants to sign off on the park -- including Malcolm, Ian Grant and Ellie Sadler -- as well as his two grandchildren, who eventually get lost in the park with Grant.

The details, however, paint a decidedly more sinister figure. The book’s version of Hammond is a cold-hearted profiteer who can see only money in the park and cuts considerable corners in its construction. That’s what leads disgruntled employee Dennis Nedry to disrupt the park’s functions in a bungled attempt at industrial espionage. Even when his grandchildren are imperiled, Hammond cannot take responsibility for the disaster. Indeed, he’s actively contemplating building a second park when he slips down a hill and gets eaten by a pack of tiny Compsognathus: devoured by his own creations run amuck.

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How the Jurassic Park Film Changed John Hammond

Dr. Sattler, Dr. Malcolm. Dr. Grant, Dr. Wu and John Hammond with a Velociraptor egg in Jurassic Park

Hammond’s character underwent a drastic change in the movie version of Jurassic Park, putting him more in line with Spielberg’s signature humanism. According to Joseph McBride’s biography Steven Spielberg, the director deeply identified with Hammond's showmanship. Koepp thus changed him to be a far warmer and friendlier personality closer to Spielberg in outlook and temperament. That started by casting Richard Attenborough, who not only brought a grandfatherly demeanor to the part but was actually an accomplished director himself, winning the Best Director Oscar for Gandhi in 1982 against Spielberg’s work in E.T.

With that came numerous other changes. The movie's Hammond is far more concerned about his grandchildren than he was in the book. And he views the park as an act of philanthropy -- a gift to the world -- rather than something solely designed as a cash cow. That induces him to ultimately denounce the park at the end of the film along with the other protagonists, leaving him a chastened humanitarian rather than a callous capitalist. Other characters assume the burden of his villainy, from Nedry, whose financial problems are not of Hammond’s doing, to the lawyer Gennaro, who sees only dollar signs and gets gobbled up by a T. rex for his sins. Hammond himself survives past the end credits and remains out of the action for the remainder of the series, reflecting his improved morals.

His literary death, however, was too good to go to waste. Spielberg and Koepp used it in the sequel, The Lost World: Jurassic Park, with Peter Stormare’s sinister InGen operative taking Hammond’s place as the Compsognathus’ dinner.