True story: Nathan Fillion is in Guardians of the Galaxy. Director James Gunn and the actor have both confirmed he has a small role in Marvel's upcoming space adventure. Here's another true story: Nathan Fillion isn't playing Nova or Cosmo, despite rumors to the contrary.

“There’s so much bullshit on the internet," Gunn tells Nerdist. "I woke up – first it’s ‘Nathan’s Nova!’, then there are articles all over saying Nathan’s Cosmo. It’s like, ‘What?!’ Nathan’s role is a very small cameo that I wanted to give to Nathan because I love working with him and I think it’s lucky for me to have Nathan in all of my movies. At the same time I wanted to give him something where Nathan could have a larger role in the Marvel Universe if either Joss [Whedon] or I or whoever chose to do that in the future. Which I would love to do. I would love to give Nathan something he could really chew on, but it didn’t work out on this movie for two reasons. Number one — because he was shooting Castle. And number two, because it just wasn’t the right exact role for him.”

As for Fillion ... well, the Firefly veteran is a little disappointed by the rumor mill. "With so much inaccurate 'news' about my involvement in GOTG, I'm actually losing faith in the internet," he wrote last week on Twitter. "I'm not Cosmo.

Opening Aug. 1, Guardians of the Galaxy stars Chris Pratt, Zoe Saldana, Bradley Cooper, Vin Diesel, Dave Bautista, Djimon Hounsou, Michael Rooker, Karen Gillan, Benicio Del Toro, Josh Brolin, Glenn Close and John C. Reilly.