After the first full trailer for Marvel’s latest action pic “Guardians of the Galaxy” was released Monday, some of the film’s stars gathered for a Facebook Q&A.

Chris Pratt, Karen Gillan, Vin Diesel, Dave Bautista, James Gunn and Kevin Feige were all on hand to discuss both fun and personal topics with fans. Diesel also opened up about his late “Fast and Furious” co-star Paul Walker.

The actor, who voices Groot in the film, said the most challenging thing about getting into character was getting back to work right after his friend’s death last November.

“It was very personal- it was the month after the accident happened with my brother Paul Walker and it was the first time I had worked since,” he said.  “Although it was challenging, just to get back to work was therapeutic- especially as Groot. There was an innocence about the character that was just refreshing- and it may have been more challenging under other circumstances, but at that time, it was very therapeutic.”

Helmer Gunn reassured those who may not be up to speed on all things Marvel, saying, “Go in fresh, the movie makes sense whether or not you’ve read the comics.”

Gunn also said the film contains some of his favorite things, making it a natural fit.

“I love raccoons, Marvel comics, and space operas. How could I pass this up?” he said, adding, “At one point in time our producers Jeremy Latcham and Jonathan Scwartz thought I was biologically engineered to make this movie. It’s everything I love.”

Diesel said Pratt is the class clown on set, calling his co-star “refreshingly hysterical.”

Gillan also discussed her reaction to her dramatic transformation after shaving off her hair for the role of Nebula.

“I fell asleep for two hours in the chair while they cut it off,” Gillan said. “When I first woke up, I was fine and then when I woke up the next morning I was like WHATTTT!”

Marvel’s “Guardians of the Galaxy” bows Aug. 1.