The idea for the surprising box office smash Oppenheimer first came to writer-director Christopher Nolan by way of Robert Pattinson, when Pattinson gifted him a book of J. Robert Oppenheimer speeches as a Tenet wrap gift.

From there, Nolan read American Prometheus: The Triumph and Tragedy of J. Robert Oppenheimer, the Pulitzer Prize winning biography of the physicist. Written by historians Kai Bird and Martin J. Sherwin, the book was released in 2005, and 18 years later, has gaining traction once again as the basis for Nolan’s biographical epic — it’s currently #2 on Amazon’s book charts and making its way back up the New York Times Best Sellers lists.

At 721 pages, the movie’s large scope makes a lot more sense. It’s three hours long, features 79 actors in speaking roles (including Cillian Murphy, in the title role), and covers over 33 years of Oppenheimer’s life.

If a 700+ page book just isn’t in the cards for you, our Senior Film Reporter Anna Menta wrote about a documentary that’ll help make sense of the physicist’s life without the non-linear timelines Nolan uses.

Either way, we definitely recommend supplementing your Oppenheimer viewing with something to help you make sense of the timeline and historical figures that appear in the movie. Right now, you can get American Prometheus for 36% off on Amazon.

First and foremost, Oppenheimer is based on J. Robert Oppenheimer’s life, but to write the movie’s screenplay, Nolan adapted the biography American Prometheus.

Like the movie, the book covers Oppenheimer’s early years studying physics abroad before returning to the US, teaching at U.C. Berkley, being recruited for the Manhattan Project, building the first atomic bomb, the Trinity Test, plus what happened after: the security clearance hearing, tension with Lewis Strauss, and his Enrico Fermi Award.

(The cover of American Prometheus, which features a black and white close-up photo of Oppenheimer may look familiar to movie fans, too, since the first-look image released before Oppenheimer was a photo of Murphy recreating the image.)

Right now, you can get a Kindle e-book of American Prometheus, the book that inspired Oppenheimer, for $15 and a paperback copy for $16, both down from an original price of $25.

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