According to the report from Entertainment Weekly, the special was filmed in Belfast earlier in the year and hosted by Conan O'Brien. It will not air on HBO, but on the complete box set of the high-fantasy series, which, obviously, won't become available until the show wraps up its eighth and final season in the new year.
While not many details are known about the special or whom it will feature, we do know that Sean Bean (Ned Stark) is set to make an appearance, alongside the principal players of Season 8.
So who else could turn up? Well, there's no shortage of possibilities — after all, no reunion special would be complete without, say, Jason Momoa (Khal Drogo), Michelle Fairley (Catelyn Stark), Richard Madden (Robb Stark), Pedro Pascal (Prince Oberyn), Charles Dance (Tywin Lannister), Rose Leslie (Ygritte), Kristian Nairn (Hodor), Ciarán Hinds (Mance Rayder), Aidan Gillen (Petyr Baelish), Jack Gleeson (Joffrey Baratheon), Mark Addy (Robert Baratheon), Natalie Dormer (Margaery Tyrell), Finn Jones (Loras Tyrell), and many, many others.
Season 8 of Game of Thrones will consist of six episodes, the first of which premieres on HBO in April.