James Gunn is hard at work on a third Guardians of the Galaxy film, and it sounds like the returning filmmaker is far along in the writing process for the sequel.

In a post on his Facebook account, Gunn revealed that he has been writing the Guardians sequel for over a year and that he's currently in the middle of rewrites of the rough draft for the full script to submit to Disney. "I'm more than a year into the process, so the script is far along. For many many months I first write the treatment which is 80 pages or so with photographs," he explained. "That turns into GotG - I'm now rewriting and making sure my rough draft works."

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While the proposed Disney acquisition of many of Fox's properties, including cinematic licensing to the X-Men and Fantastic Four, is expected to be completed by the summer of 2019, Gunn added that he currently has no plans to integrate characters from those properties into the upcoming film.

"Not gonna happen in any major way. Too far along," he replied when asked if he planned to include any Fox-licensed characters, later confirming he has already selected the characters for the sequel. When asked if Vol. 3 would feature an appearance by the titular anti-hero from Sony's upcoming Venom, Gunn pointed out that Marvel currently doesn't have the cinematic licensing to the character, nixing the chances of Groot encountering an alien symbiote.

Nevertheless, one major element of Vol. 3 that Gunn hasn't completely finalized yet is the soundtrack; the classic rock tracks personally selected by Gunn, of course, have played a major role in the previous two films.

"Mostly. But I've also changed it a lot, so who knows!" answered Gunn when asked if he assembled a soundtrack for the sequel.

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Gunn's update lines up with comments from Guardians star Chris Pratt this past week that filming on a third Guardians of the Galaxy movie would begin in January for a 2020 release date.

In the meantime, the Guardians can be seen taking on Thanos in Avengers: Infinity War in theaters now. While most of the interstellar superteam met an ominous fate in the Avengers sequel, the Infinity War follow-up next year all but assures their return.