U.K. retailer Asda has "hired" Buddy the Elf in this year's Christmas campaign, creating an entirely new story out of scenes from the original Will Ferrell movie.

In a TV spot involving some ingenious visual effects, the supermarket chain took original footage, lines and actions from "Elf" and placed the character at the heart of a bustling Asda store as its newest recruit. Ahead of the launch, the campaign theme was teased by Asda running recruitment ads in newspapers for a new "extra special Christmas colleague" who's "joyful, kind and likes to smile."

The 90-second film, created via agency Havas U.K., veteran director Danny Kleinman of Rattling Stick and post-production company Framestore, opens with a homage to Elf’s iconic ‘"street crossing" scene. This time, it’s a bunch of Asda shopping carts, rather than a New York City cab, that causes Buddy to exclaim “sorry!” as it crashes into him. 

The ad goes on to show Buddy causing chaos on his trial shift, singing loudly over the store loudspeaker system and, similar to the movie, decking out the entire shop floor in fairy lights and festive decorations overnight while re-christening the self-checkouts as "elf checkouts." In each scene, Buddy interacts seamlessly with Asda employees using footage from the movie.

After the TV ad breaks Friday night on U.K. TV in ITV's "Coronation Street," Asda customers will hear in-store announcements from Buddy himself, and there will be Asda-exclusive Elf-themed food and clothing.

It's the first time "Elf" has ever been licensed for brand marketing; Ferrell has famously refused to make a sequel to the 2003 movie and is known to be very protective of the character.

According to Havas U.K. Chief Creative Officer Vicki Maguire, the agency worked closely with the star, who saw "every version" of the script, plus "Elf" director Jon Favreau and Warner Bros. Discovery Global Consumer Products. Licensing of "Elf" was managed by David Born and Amber Cheung at Born Licensing and Will Ferrell by Talent Republic. Ferrell agreed to the ad after briefings about Asda's business and in particular, about its community projects. 

The team had to ensure that everything was true to the original movie, right down to the food that Buddy eats. For example, for a scene in the ad where Buddy eats pigs in blankets, Ferrell pointed out that Buddy doesn't eat anything that isn't sweet or sugary. So, Asda suggested its pigs in blankets with maple syrup. (The scene in which he eats them was recreated from the movie scene where Buddy eats chewing gum in the subway.)

"We had to use everything in the film," said Maguire, who said she watched the film "multiple times" in order to pick out the most pertinent lines. 

The spectacular post-production by Framestore rotoscoped Buddy out of the original film, then helped fit an entire new world around him; no deepfake was allowed to be used.

Danny Kleinman's attention to detail made him the perfect choice to direct the film, said Maguire, as he focused on fine points such as knowing what lens Favreau used in the original footage and what grade was used in the original scenes. "We needed someone who was really going to geek out on how to bring it to life."

Kleinman commented in a statement: "For me this was a unique challenge, working with an A list Hollywood actor, without him being there in person, and crafting other actors around his iconic performance. It was important not only to make the action seamless but also convincingly transport him to a Christmas Asda store, creating a Hollywood feel to Asda’s Christmas celebrations.”

Asda isn't the only retailer leaning into movie nostalgia this holiday season; in the U.S., Walmart (which once owned Asda) this week launched a holiday campaign that resurrects the cast of the 1999 movie "Office Space.

To find out more about how Asda made the "Elf" ad, you can watch the brand's Behind the Scenes video, below.