The Prince and Princess of Wales made a special trip to the MGM Music Hall on Friday ahead of the second annual Earthshot Prize awards ceremony.
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In preparation for the star-studded event, Princess Kate confidently took to the circular stage decked out with spectacular floral displays and impressive lighting.
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The stunning behind-the-scenes black and white photo shows Princess Kate wearing a sleek satin skirt and a fine knit jumper. The royal elevated her sophisticated look with some heeled boots and a pair of statement drop earrings.
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A second photo shows Prince William enjoying a light-hearted moment with a member of the production team, whilst a third photo includes a sign to the stage along with the words: "The Earthshot Prize, To MGM Stage Left".
And over on Twitter, Prince William and Princess Kate penned: "Less than 12 hours to showtime...#EarthshotBoston 2022".
The Princess of Wales is prepping for this evening
Kate's unofficial engagement preludes Friday's glittering Earthshot Prize awards ceremony. Dubbed Prince William's "Superbowl moment," the glitzy ceremony is expected to draw an A-list crowd at the MGM Music Hall at Fenway in Boston.
The ceremony will be filmed on Friday but won't be aired until Sunday evening via the BBC at 5.30pm. Luckily for royal fans around the world, the ceremony will be made available on YouTube from 6pm on Sunday.
Among those presenting awards are the Oscar-winning actor Rami Malek, Home Alone and Schitt's Creek star Catherine O'Hara and environmental activist and Big Little Lies star Shailene Woodley.
Prince William appeared in high spirits
Earthshot Prize council members Sir David Attenborough and Cate Blanchett will both provide voiceovers during the ceremony, which will be presented by UK broadcaster Clara Amfo and US actor Daniel Dae Kim.
Ambassador Caroline Kennedy, daughter of President John F Kennedy, whose "Moonshot" speech about space travel inspired the Earthshot prize, will also take part with her son Jack Schlossberg, JFK's only grandson.
The ambitious, decade-long, global Prize programme aims to discover and scale up solutions to the planet's biggest environmental challenges.
The spectacular event kicks off on Friday evening
Among the ideas competing this year are a cleaner-burning stove initiative in Kenya and a bubble barrier made in the Netherlands to prevent plastics entering oceans.
William described the finalists as "innovators, leaders, and visionaries" and said they proved there are "many reasons to be optimistic about the future of our planet".
He went on to say: "They are directing their time, energy, and talent towards bold solutions with the power to not only solve our planet's greatest environmental challenges, but to create healthier, more prosperous, and more sustainable communities for generations to come".