She may have been The People's Princess, but there was much Diana, Princess of Wales, kept from the public's prying eye — intimate details catalogued in author Kate Snell's 2000 account "Diana: Her Last Love," the inspiration for the upcoming film starring Naomi Watts.

The film spans the final two years of Diana's life, before she — along with companion Dodi Fayed and driver Henri Paul — was killed in a car accident in Paris in 1997. At the center of "Diana" is the secret affair the Princess carried on with surgeon Hasnat Khan (played by "Lost" actor Naveen Andrews).

A new trailer for the biopic captures this clandestine romance, juxtaposed against the demands of Diana's high-profile persona. The clip opens with the Princess engaged in her royal and philanthropic duties — walking red carpets and crusading against land mines. But soon we see her meet Dr. Khan, telling him in no uncertain terms: "Charles and I live separate lives." Thus begins the under-the-table hand-holding, wig-wearing and secret rendezvousing, which, in a story familiar to us all, culminates in salacious tabloid headlines the world over.

And while her last beau, Fayed, is introduced in the clip's closing moments — and, as it's hinted at, used to make Khan jealous — it's clear Diana's love affair with the good doctor is the beating heart of this film.

"Diana," directed by Oliver Hirschbiegel and adapted by screenwriter Stephen Jeffreys, bows November 1.