Heidi Klum. Photo by Willy Sanjuan/Invision/AP

Heidi Klum has become known for the stunning and intricate costumes she dons for the spooky holiday celebrated on 31 October, and has taken to Instagram to reveal this year's design is already underway.

Heidi posted a video on the photo-sharing site on Tuesday which showed a prosthetic mould being made of the lower half of the beauty's face, as well as her neck and shoulders.

She captioned the clip: "Getting ready for #heidiklumhalloween2018 @prorenfx (sic)"

The 'America's Got Talent' judge always keeps her costume a secret until the big reveal at her annual Halloween party, so fans will have to wait a little longer to see what the prosthetics are going to be used for.

Last year, Heidi paid homage to Michael Jackson's 'Thriller' music video when she dressed as a werewolf, and admitted she had been planning the outfit since June.

Heidi Klum, dressed as a werewolf from Michael Jackson's "Thriller" video, attends her 18th Annual Halloween Party at Moxy Times Square on Tuesday, Oct. 31, 2017, in New York. Picture: AP

She said at the time: "I like to keep it fun, you know. I usually start planning in June. It's not just going to be just getting dressed easily, I always have a lot of prosthetics done with these amazing people that do this for me."

And speaking the day before Halloween last year, the blonde beauty said she would spend a whopping six hours getting into costume on the big day.

She said: "Tomorrow I'm going to be there for six hours gluing all this stuff on. I have a lot of stuff being glued, yeah. Because last year I didn't do anything, I was me with five clones, which I thought was just a fun idea."

In 2016, Heidi hired five other women to accompany her to her party, who all donned synthetic replicas of her own face to create an army of Heidi Klums.

Speaking about her costume at the time, she said: "This came about because everyone always says, 'How do you juggle it all? How do you juggle it all?' I'm always thinking, 'I wish there were more of me so I could have it much easier.' One could stay at home, the other one could go work! So that's how it happened! It's six-times me today!"

Previously, the 'Project Runway' host also stunned party-goers in a prosthetic heavy Jessica Rabbit costume.