According to Hypable on April 7, at the St. Louis Wizard World Comic Con, "Castle's" Nathan Fillion made his appearance. He showed up at a mini "Firefly" reunion with this cohorts Adam Baldwin and Alan Tudyk where they talked about old times, jokes they played on each other on the set, and more.
“Wanting to get a part… or maybe did. “I’m just saying maybe. Maybe you’ll be surprised. Maybe. Check the credits".
The crowd of fans went wild at Fillians tease and the avid tweeting Gunn responded on his Twitter account as a result:
"There is a cat running around my office let out of his respective bag. I have a feeling @NathanFillion has been in here".
The convention in St. Louis also had guest stars such as "Batman's" Adam West and Burt Ward, "Doctor Who’s" Karen Gillan and Matt Smith, as well as "Lord of the Ring's" Sean Astin. Notably Gillan will also be appearing as Nebula in Gunn's Marvel Studios film and will be pairing off with Gamora portrayed by Zoe Saldana.
That being said, "Guardians of the Galaxy" appears in theaters Aug. 1.