Marvel Studios president and producer Kevin Feige teased new details regarding Guardians of the Galaxy, including one intriguing tidbit that Zoe Saldana's Gamora starts out as a villain working with Ronan, Nebula and Korath.

"They are an unlikely band. It's pure circumstance that brings them all together throughout the course of the movie. Rocket has been genetically and mechanically altered, he's an experiment from one part of the galaxy. Groot is a species that happens to look like trees look, and is quite communicative if you can understand the different inflections in the way he says, 'I am Groot.' Peter Quill left Earth in the mid'80s, but when we meet back up with him he's very much a citizen of the universe. Drax has one goal and one goal only, which is to kill Ronan because of a past tragedy. When we meet Gamora, she's a bad guy working with Ronan and Nebula and Korath, and by extension for Thanos. Gamora doesn't necessarily like doing that anymore, and tries to find a new path for herself. But she has a reputation as the deadliest woman in the galaxy that people aren't greeting her with open arms."

Earlier this summer, Marvel Studios issued 2016 and 2017 release dates for three projects which have yet to be identified. When asked when the fans will know what these projects are, Kevin Feige revealed that answers are coming next spring.

"Next spring is when we really sit down and start to decide what we announce for 2016 and 2017. There are three or four slots. We've got six or seven things going. We've got to choose which four will go. It's a Battle Royale!"

He also teased that Mark Ruffalo's Hulk is getting a bigger role in The Avengers: Age of Ultron.

"I think we have something special with our Mark Ruffalo Banner, and we'd love to see where we could take his stories."

When asked about Jeremy Renner's Hawkeye, the producer said that writer-director Joss Whedon has an expanded story line for him as well in The Avengers: Age of Ultron.

"Joss has a great storyline in mind for him that shows a deeper side and further fleshes out our favourite archer."