Sir Michael Gambon and Alan Rickman ruined a key Harry Potter scene just to prank Daniel Radcliffe

Sir Michael Gambon and Alan Rickman once ruined a key Harry Potter scene just to prank Daniel Radcliffe, with co-star Emma Watson saying the moment was ‘really funny’.

Watch the incredible prank in action below:

Earlier today, it was announced that Gambon had died at the age of 82, following a ‘bout of pneumonia’.

A statement on behalf of his wife Lady Gambon and son Fergus Gambon, issued by publicist Clair Dobbs, said: “We are devastated to announce the loss of Sir Michael Gambon.

“Beloved husband and father, Michael died peacefully in hospital with his wife Anne and son Fergus at his bedside, following a bout of pneumonia. Michael was 82.

“We ask that you respect our privacy at this painful time and thank you for your messages of support and love.”

In the wake of the sad news, many fans have been remembering his finest moments – including in scenes that didn’t quite make the final cut.

While on the set of Harry Potter and the Prisoner of Azkaban, directed by Alfonso Cuaron, Gambon teamed up with Rickman to play a hilarious prank on a young Daniel Radcliffe.

Warner Bros

Sadly, the hilarious moment never made it into the film, but thankfully, the cameras were still rolling.

Speaking about the practical joke in the DVD extras, Radcliffe recalled: “There was one time where, in this room actually, Michael Gambon and Alan Rickman, and I think Alfonso was co-ordinating it, took the opportunity to play a practical joke on me.”

As it dawned on co-star Emma Watson what he was talking about, she put her head in her hand, saying it was ‘really, really funny’.

Radcliffe cut in: “For you!”

The cast had been filming a scene where Hogwarts students were sleeping on the floor of the castle’s great hall.

Cuaron said: “It was very good because it was a bunch of sleeping bags and Dan asked us to have his sleeping bag next to this particular girl that he fancied.”

The clip then cuts to the scene in question, with Gambon and Rickman walking through the sleeping students as Dumbledore and Snape.

Suddenly, a fart noise goes off, prompting Radcliffe to start sniggering as he tries to pretend to sleep – while Gambon continues with his lines.

Warner Bros

The farting sounds continued as Gambon hilariously carried on, with Radcliffe remembering: “We’d just finished a take, it’s taken ages to get it.

“They had put a fart machine into my sleeping bag, and Michael Gambon had actually been pressing it during the take, I found out.”

Watson added: “This hall echoed!”