Harry Potter fans rejoice! Professor Slughorn could be making a small screen debut on HBO series Game of Thrones as Jim Broadbent hints he is starring as an "old professor".

The Harry Potter star, 67, was confirmed to be joining the GoT cast last year, though details of his role on the hit series were not yet revealed.

Now, the British national treasure has opened up to ScreenCrush about his new character, teasing that many of his scenes are with Samwell Tarly – who is played by John Bradley-West. Hmm... interesting.

The publication speculated that Broadbent's character could be Maester Marwyn or perhaps a maester of another name who will fill the role of the character from George R Martin's book series. GoT fansite Watchers on the Wall suggests he could play Archmaester Ebrose, but nothing has been confirmed.

Broadbent revealed: "I'm a maester, an archmaester. I'm an old professor character." Could Pro Slugworth be making a comeback? He went on to state how many episodes he is appearing in, adding: "I did five episodes. I did sort of one major scene in each episode."

It is also not known when season seven will hit screens, though Liam Cunningham – who plays Ser Davos Seaworth – suggested it could be as late as July.

He recently said: "I've been disappointing various people around the world because it was meant to come out in April. It's July now, I think," and backed up his statement on Twitter by posting: "Davos don't know date. Mongo only pawn in Game Of Thrones. #gameofthronesseason7".

The only details we do know about the upcoming season is that it will have a shorter run of seven episodes and it will be "absolute chaos" according to Grey Worm actor Jacob Anderson.

A new "in production" teaser also got fans excited as it showed a mysterious hand holding the Oathkeeper. The Valyrian steel sword was given to Brienne of Tarth by Jamie Lannister.

Game of Thrones season seven will launch on HBO in the US and on Sky Atlantic in the UK.