Spencer trailer: Kristen Stewart delivers emotional performance as Princess Diana

Kristen Stewart as Princess Diana. Photo / NEON films

The first full-length trailer for Spencer has arrived - and it looks like it will be a tearjerker.

The two-minute look at Pablo Larrain's film starring Kristen Stewart as the late royal begins with the Queen asking: "Is he here yet?"

"Three days. That's it," Diana says to herself in the bathroom mirror as she prepares for a Christmas at Balmoral. The movie is set over three fateful days in the life of the Princess of Wales.

We see Stewart tap into Diana's emotional plight as she puts on a brave public persona despite struggling on the inside.

"You have to be able to do things you hate. There has to be two of you - the real one, and the one they take pictures of," Prince Charles, played by actor Jack Farthing tells her a snippet from the movie.

The actor who plays a young Prince William (Jack Nielen) delivers a heartbreaking line: "Mommy, what's happened to make you so sad?"

Early critical reception has sung praises for the film after it premiered at Venice Film Festival.

Kristen Stewart as Princess Diana. Photo / NEON films

The New York Post's critic wrote: "[It] gets to the meat of what was tormenting the People's Princess better than any simple historical retelling ever could."

A reviewer for the UK's Daily Telegraph said: "Its focus rests on its heroine alone. But what a heroine - and what thrillingly gutsy, seductive, uninhibited filmmaking this is."

The Guardian gave the film five stars, and praised Larrain's approach.

The movie follows just three days in the life of Diana, during Christmas time at the royal family's Sandringham estate when she decides to leave Charles.

The synopsis of the film reads: "December, 1991: The Prince and Princess of Wales' marriage has long since grown cold. Though rumours of affairs and a divorce abound, peace is ordained for the Christmas festivities at Sandringham Estate. There's eating and drinking, shooting and hunting. Diana knows the game. This year, things will be a whole lot different."

Larrain, the famed Chilean director also directed Jackie, which starred Natalie Portman as Jackie Kennedy.

• Spencer is coming to New Zealand cinemas on January 27, 2022