Four months after Game of Thrones author George R.R. Martin revealed that a fifth Game of Thrones prequel spin-off is being developed, we finally know who's working on the series. Bryan Cogman, a longtime Game of Thrones writer and producer has been tapped to develop this series alongside author George R.R. Martin, although, unfortunately, no plot details have been given at this time. It remains to be seen which of these shows will actually be picked up to series, once the final season airs in either 2018 or perhaps 2019.

In early May, HBO confirmed that these four Game of Thrones spin-offs are happening, with the network bringing in writers Max Borenstein (Godzilla, Kong: Skull Island), Jane Goldman (Kick-Ass, Kingsman: The Golden Circle), Brian Helgeland (Mystic River, L.A. Confidential) and Carly Wray (Mad Man) to develop these shows. Then just a few weeks later, George R.R. Martin revealed on his blog that he's involved with all of the shows, instead of just two as originally reported, and that there is a fifth show in the works, with the writer to be announced once his deal has closed, which has now apparently happened. Entertainment Weekly broke the news today, making Bryan Cogman the only other member from the current Game of Thrones creative team to be involved in these spin-offs.

Bryan Cogman joined the hit series in the first season, as an assistant to Game of Thrones creators David Benioff and D.B. Weiss, but he quickly rose up the ranks. He has written 11 episodes for the hit series, including "Kissed by Fire," which featured Jaime Lannnister's (Nikolaj Coster-Waldau) bathtub confession to Brienne of Tarth (Gwendoline Christie), "The Laws of God and Men," which centered on the trial of Tyrion Lannister (Peter Dinklage) and the Season 7 premiere, "Stormborn." IMDB also lists him as being the writer for the second episode of Season 8. He also rose to a story editor post in Season 2, an executive story editor in Season 3, co-producer in Season 4, producer in Season 6, supervising producer in Season 6 and co-executive producer in Season 7.

Unfortunately, this new report doesn't shed any light on what this series may be about. The only thing we know thus far is what these shows won't be about, with George R.R. Martin confirming in May that none of these shows will follow his Dunk & Egg characters, from a series of novellas the author has written, set 100 years before the events of the show and the original books. The author also revealed the shows will not center on Robert's Rebellion, when Robert Barantheon (Mark Addy) overthrew the Mad King, Aerys Targaryen, ending over 300 years of Targaryen rule on the Iron Throne. The author added that, once he finishes his A Song of Fire and Ice book series, fans will know everything they've ever wanted to know about Robert's Rebellion.

It has also been confirmed that none of these shows will use members of the current Game of Thrones cast, with George R.R. Martin stating in May that these programs aren't exactly spin-offs, since they don't feature existing characters. He revealed that he refers to them as "companion shows," although at this point, that's about all we know thus far. Regardless, it's clear that these shows have been left in good hands with the writing team that has been assembled.