Her final love: Naomi Watts and Naveen Andrews show the romance of Princess Diana and her heart surgeon lover in new trailer

In a new theatrical trailer for the upcoming Princess Diana biopic, the world gets a closer glimpse at the secret relationship between the tragic royal and her heart surgeon love.

Naomi Watts proves herself yet again as the perfect star to take on the role of the Peoples' Princess, with Naveen Andrews as Dr. Hasnat Khan, the last man she ever loved.

Focusing on the public pressure and media spotlight affecting their romance, the trailer proves to be a harrowing insight into the movie's focus on the private life of the former Princess of Wales.

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Secret love: In the new trailer for Diana, it gives a closer look at the central story of the Princess's romance with Dr. Hasnat Khan

Secret love: In the new trailer for Diana, it gives a closer look at the central story of the Princess's romance with Dr. Hasnat Khan

The production have done well to recreate classic images of Diana throughout the film, focusing on the last two years of her life as she continued her charity work, supporting AIDS victims and campaigning against landmines with the Red Cross.

But it was her little known relationship with a heart surgeon that grips our attention as the truth behind their failed union comes out in the trailer.

At first, Diana's attraction to Khan stems from his treatment of her as a normal person, with her saying to a friend: 'He doesn't treat me like a princess, it's almost like he doesn't know who I am.'

Normality: Diana loved Hasnat for not treating her like a princess

Normality: Diana loved Hasnat for not treating her like a princess

Commoner: Naveen Andrews plays the heart surgeon Diana fell in love with

Commoner: Naveen Andrews plays the heart surgeon Diana fell in love with

 

And while the trailer shows a montage of clips of the two enjoying the early stages of their romance, it seems the media attention surrounding the princess was far too much for Hasnat to handle.

'If I marry you, I have to marry the whole world too,' the doctor tells Diana as the invasion of her privacy from the paparazzi becomes more apparent, with the royal running from cameras and headlines featuring her relationship with Khan.

But after the end of her romance with the heart surgeon, it shows the start of her fling with Dodi Fayed, who is not portrayed as a serious love of Diana's, but rather a playful rebound to help her get over Hasnat.

Escape: The film shows moments of solitude between the star-crossed lovers away from the media's eye

Escape: The film shows moments of solitude between the star-crossed lovers away from the media's eye

Public engagement: Diana met Hasnat through her charity work in the last two years of her life

Public engagement: Diana met Hasnat through her charity work in the last two years of her life

Media attention: Putting Khan in the spotlight put a strain on her relationship with the doctor

Media attention: Putting Khan in the spotlight put a strain on her relationship with the doctor

However, as history shows, Dodi - played by Cas Anvar - was the last man Diana was ever seen with before the fatal car crash of 1997 that claimed her life in Paris.

Also playing supporting roles in the biopic are Juliet Stevenson as Sonia, a character created from an amalgam of Diana's friends, and Douglas Hodge as Paul Burrell, the princess's butler.

The film is directed by Oliver Hirschbiegel - who made the critically acclaimed Downfall which portrayed the final days of Adolf Hitler's life - with a screenplay by playwright Stephen Jeffreys.

Charity work: The film creates classic images of Diana in the field campaigning against landmines

Charity work: The film creates classic images of Diana in the field campaigning against landmines

Hasnat Khan
Dodi Fayed

Her final beaus: Naveen Andrews and Cas Anvar play the doctor and the billionaire who loved Diana last

Rebound: After her failed romance with Khan, Diana started seeing Dodi Fayed

Rebound: After her failed romance with Khan, Diana started seeing Dodi Fayed

Championing his partner in the central role is Liev Schreiber who recently told E! News: 'I think you can expect, well, what we've all come to expect from Naomi, which is nothing but excellence.

'I haven't seen the film. I've seen some outtakes, I've seen some scenes and she looks fabulous. I mean, she looks, sounds, feels like Diana and I'm really looking forward to it.'

Diana is scheduled to hit theaters in the U.K. on Sept. 20, with a U.S. release set for Oct. 10.

Too much to handle: In the end the public gaze turned out to be the People's Princess's demise

Too much to handle: In the end the public gaze turned out to be the People's Princess's demise