Derek Hough has claimed he stole "a Ravenclaw robe, scarf, tie" and "silverware" from the set of 2001's 'Harry Potter and the Philosopher's Stone'.

The 39-year-old actor-and-dancer and his sister Julianne Hough, 36, were extras in the first movie in the blockbuster wizarding franchise based on the books by J.K. Rowling, which is called 'Harry Potter and the Sorcerer's Stone' in the US, and he has confessed to swiping a number of items as keepsakes from his time as a student at Hogwarts.

Sharing a clip of the pair in the film, he wrote on Instagram: "Did you know @juleshough and I were in the first Harry Potter film?

We spent three months in the Great Hall, the Forbidden Forest, and even the Quidditch pitch!

It was incredible to be part of such a historic moment. And I may have 'accidentally' taken a Ravenclaw robe, scarf, tie, and a few pieces of silverware from set… but shh, don't tell!

Just a little holiday magic and nostalgia to share with you all. Happy holidays #harrypotter."

Derek - who went on to become a pro on 'Dancing with the Stars' - also revealed that he was a stand-in for Slytherin bully Draco Malfoy (Tom Felton).

Referencing Draco's famous quip, he added in the comments: "Also , I stood in for Draco Malfoy to set up shots. PPPPPOTTER ! (sic)"

Several celebrities have made cameos in the 'Harry Potter' films, including former Little Mix star Jesy Nelson and 'Bridgerton' star Rege-Jean Page, to unlikely stars such as Stone Roses frontman Ian Brown, who played an unnamed wizard sitting in the Leaky Cauldron pub.

Derek isn't the only actor to swipe props from the set of the films.

The late Alan Rickman - who starred as Slytherin's Severus Snape in all eight films - pinched gold coins from Gringotts Bank, according to co-star Jason Isaacs (Lucius Malfoy).

He told BANG Showbiz: "It was very difficult to steal things because Alan (Rickman) god love him, god rest his soul. He nicked all of the Gringotts coins on the very first day he did Goblins and swiped in and out like a supermarket. I couldn't get away with it."

Jason was also left embarrassed after a failed attempt to swipe a copy of wizarding newspaper The Daily Prophet.

He admitted: "I once tried to take a copy of The Daily Prophet because there were thousands of them. I said I'd like one of those to director David Yates, who said, 'No problem mate'.

"I put it in my bag and when I got to the gates, they said, 'David said can he have it back'. It was so embarrassing. So I got nothing."