One of the most horrific moments in sci-fi film history is the "chestburster" scene in Alien. Now, thanks to a new book, we know what inspired that nightmarish sequence.

A newly published book called Shock Value: How a Few Eccentric Outsiders Gave Us Nightmares, Conquered Hollywood, and Invented Modern Horror, by New York Times journalist Jason Zinoman, recounts the history of the modern horror film circa the late '60s and '70s—when horror auteurs like John Carpenter, George A. Romero, Tobe Hooper and David Cronenberg were rising through the ranks. A large section of the book is devoted to the relationship between Carpenter and writer/director Dan O'Bannon, who made one movie together (the cult classic Dark Star) before going their separate ways.

O'Bannon (who died in 2009) went on to write the script for Alien, but what wasn't widely known is that he suffered from Crohn's disease, a debilitating digestive disorder. According to Zinoman's book, "the digestion process felt like something bubbling inside of [O'Bannon] struggling to get out." From his own torment came the idea for the alien bloodily punching its way out of John Hurt's chest during dinner.

The book also mentions that O'Bannon hand-picked H.R. Giger to design the alien's several stages of growth and insisted that director Ridley Scott, who was not a horror fan, look at The Texas Chain Saw Massacre in order to get a feel for what he had to accomplish.

There are apparently many more anecdotes of this sort in Shock Value, so we'll be picking up a copy as soon as possible. And the next time you watch Alien, remember poor Dan O'Bannon and how his own illness inspired one of sci-fi's most awful deaths.

(via The New York Observer)



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