With ‘Game of Thrones’ expected to premiere its sixth season next spring, speculations of fan-favorite characters returning to the hit HBO series have been gracing the deadlines; these include the return of Catelyn Stark’s uncle, Brynden Tully.

The last time fans were able to check in with “The Blackfish” had been in ‘Game of Thrones’ season three during the Red Wedding. While Catelyn, her son Robb and many other allies of the Stark family were viciously massacred, Brynden was able to escape from the scene as he left the event to use the bathroom right before all the chaos had been let loose.

Los Siete Reinos is now claiming that actor Clive Russell, who took on the role of Brynden on the fantasy drama, has been spotted on the set of ‘Game of Thrones’ in Northern Ireland.

Interestingly, onlookers saw the actor all decked out in full gear, strongly indicating the possibility that he is not merely visiting his co-stars on set.

With HBO’s ‘Game of Thrones’ already catching up with the books, one of the storylines from ‘A Feast For Crows’ that have not been visited yet include The Blackfish carrying on as he holds a fortress in Riverrun.

Reports are also claiming that he and Nikolaj Coster-Waldau, who plays Jaime Lannister on the show, were spotted filming a scene in which they were particularly engaged in an intense argument, thereby suggesting that Riverrun is still in the game.

Aside from Brynden Tully, other well-loved characters are also making a comeback in ‘Game of Thrones’ season six. Actors Isaac Hempstead Wright and Kristian Nairn have also been confirmed to return as Bran Stark and Hodor, respectively.

Long-gone major character Sandor Clegane, also known as The Hound and played by actor Rory McCann, will reportedly make a comeback as well.

When it comes to dead characters showing up in ‘Game of Thrones’ season six, a young Ned Stark who is likely to appear in flashback scenes will be joined by Shae, played by Sibel Kekilli in the first four seasons. The actress, who took on the role of Tyrion Lannister’s (Peter Dinklage) lover, was spotted on set in Peñíscola, Spain, wearing clothing similar to the costumes worn by the people in Meereen.

However, it remains unclear as to how her character will be incorporated into the storyline for next season given the fact that she was already killed off in the season four finale.

Watchers on The Wall stated that the character could return as "a vision, a hallucination or a memory in Tyrion's mind combined with the sight of a Meereenese woman."

‘Game of Thrones’ season six is set to premiere on HBO in spring 2016.