Inferno

Langdon wakes up in a Florence hospital with no memory and escapes an assassin with Dr. Sienna Brooks. A projector showing Botticelli's Map of Hell starts a trail left by geneticist Bertrand Zobrist, who killed himself after creating a plague to fight overpopulation. The clues run through Dante's death mask and on to Venice. Langdon learns that the soldiers chasing him work for the WHO's Elizabeth Sinskey, and that the Consortium staged part of the ruse. In Istanbul's Basilica Cistern, the bag holding the virus had already dissolved a week earlier. The virus leaves a third of humanity sterile. Sienna, Zobrist's former lover, gets amnesty and goes to work with the WHO.

1. ChangeIn the book, the virus gets out

   In the book, by the time Langdon reaches the Istanbul cistern, the bag holding the virus had dissolved a week earlier. It leaves about a third of humanity sterile. In the film, the WHO gets there in time.

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2. ChangeSienna wants something else

   In both, Sienna deceives Langdon and goes after the virus. In the book, she wants to keep it away from the WHO, fearing it'll be weaponized. In the film, she wants to release it.

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3. ChangeSienna's fate

   In the book, Sienna gets amnesty and goes to work with the WHO on the virus. In the film, she sets off the blast in the cistern and doesn't make it out.

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