The Cambridges gave some shoppers an unexpected treat.

Kate Middleton stepped out in Norfolk on Thursday to her local Sainsbury’s supermarket to buy Halloween costumes for Prince George and Princess Charlotte, People magazine reported on Friday.

The Duchess of Cambridge, 37, and her children were spotted by locals in the Halloween clothing aisle of the Kings Lynn Hardwick supermarket. The British royals even took time to chat with stunned shoppers.

“I didn’t see what she actually bought,” local Kathy Whittaker told several U.K. newspapers, as reported by the outlet. “The lady that told me she was there had children with her and she said Kate was asking her children what they were going to be for Halloween. I think she bought some Halloween bits for her kids, but I don’t know what.”

PRINCE WILLIAM IS ‘WORRIED’ ABOUT PRINCE HARRY, MEGHAN MARKLE AFTER EMOTIONAL DOCUMENTARY: REPORT

Britain's Catherine, Duchess of Cambridge, attends a State Banquet in honour of King Willem-Alexander and Queen Maxima of the Netherlands at Buckingham Palace in London on October 23, 2018, on the first day of the Dutch King and Queen's two-day state visit. (Photo by John Stillwell / POOL / AFP) (Photo credit should read JOHN STILLWELL/AFP/Getty Images)

Kate Middleton at a state banquet in honor of King Willem-Alexander and Queen Maxima of the Netherlands in October 2018 (Getty)

According to the shoppers, Middleton, who was dressed in simple black trousers with a matching black polo neck, used the self-service check-out to make her purchases.

KATE MIDDLETON WRITES FIRST INSTAGRAM POST ABOUT ROYAL TOUR OF PAKISTAN WITH PRINCE WILLIAM

George, 6, and Charlotte, 4, are currently on a fall break from Thomas’s Battersea where they both attend. People also noted Middleton and her husband Prince William have no royal engagements next week so it seems likely the family will enjoy the Halloween festivities in their country home in Norfolk.

This isn’t the first time the royal was seen shopping at local stores solo.

Last December, Middleton was also spotted shopping at the budget-friendly store, The Range, where she bought last-minute Christmas purchases.

KATE MIDDLETON SPEAKS OUT AFTER ROYAL PLANE WAS FORCED TO TURN AROUND DURING FIERCE ELECTRICAL STORM

Britain's Princess Charlotte, left, with her brother Prince George and their parents Prince William and Kate, Duchess of Cambridge, arrives for her first day of school at Thomas's Battersea in London, Thursday, Sept. 5, 2019.

Britain's Princess Charlotte, left, with her brother Prince George and their parents Prince William and Kate, Duchess of Cambridge, arrives for her first day of school at Thomas's Battersea in London, Thursday, Sept. 5, 2019. ((Aaron Chown/Pool via AP))

KATE MIDDLETON ECHOES PRINCESS DIANA'S STYLE FOR PAKISTAN TOUR

A pal of the royal told People the future queen enjoyed a normal childhood and wants the same for her three children, including Prince Louis, 1.

“She wants to emulate her upbringing, living in the countryside with a close-knit family,” said the friend. “She desperately wants that normality for her own kids.”

In August of this year, Scotland-bound travelers got a major surprise when they saw through the plane's windows the future King of England and his family disembarking from their flight.

At the time, People magazine reported the royal family of five was seen exiting from the economy FlyBe plane, which was heading from Norwich to Aberdeen.

PRINCE WILLIAM, KATE MIDDLETON TAKE GEORGE AND CHARLOTTE TO CHEER ON ASTON VILLA VS NORWICH

Kate Middleton and Prince William pose for a photo with their three children, George (right), Charlotte (middle) and Louis.

Kate Middleton and Prince William pose for a photo with their three children, George (right), Charlotte (middle) and Louis. (AP)

KATE MIDDLETON, PRINCE WILLIAM FLY COMMERCIAL AFTER MEGHAN MARKLE-PRINCE HARRY PRIVATE JET CONTROVERSY

William, 37, and his wife got into awaiting cars with their children and their longtime nanny, Maria Teresa Turrion Borrallo.

They were heading to Balmoral, Queen Elizabeth II's summer retreat.

The eldest son of the late Princess Diana of Wales was carrying some of his bags with help from George while Charlotte happily followed them. Middleton carried Louis in her arms as she walked alongside Borrallo.

“Earlier in the flight I’d had the feeling that someone had come on the plane that I’d recognized — but I thought it was just a footballer,” a passenger told The Sun. “We landed, and people then saw two black Range Rovers on the tarmac.”

CONVICTED TORTURER GOT WITHIN FEET OF PRINCE GEORGE, KATE MIDDLETON AND PRINCE WILLIAM DEMAND PROBE: REPORT

Kate Middleton and Prince William wave to well-wishers as they leave after attending the launch of the King's Cup Regatta at Cutty Sark, Greenwich on May 7, 2019, in London, England.

Kate Middleton and Prince William wave to well-wishers as they leave after attending the launch of the King's Cup Regatta at Cutty Sark, Greenwich on May 7, 2019, in London, England. (Photo by Ben Stansall - WPA Pool / Getty Images)

KATE MIDDLETON EXHIBITS HILARIOUS FACIAL EXPRESSIONS WHILE WATCHING HISTORIC WIMBLEDON MEN'S FINAL

“Suddenly, Will, Kate, and the kids all got up, and left,” the passenger continued. “They weren’t harassed by anyone at all as they got off the plane. They just seemed like a family traveling together, to be honest. No one saw them get on the plane either. It was amazing how they did it — they must have slipped on quietly after people were already seated.”