must of any actor working for director James Gunn is the ability to do both drama and comedy, hence the casting of Chris Pratt (Parks and Recreation) as the protagonist in Guardians of the Galaxy and the selection of Bradley Cooper as the voice of the film’s “heart” in Rocket Raccoon. In reality, all of the stars of Guardans of the Galaxy bring different things to the table which makes its roster as interesting and ‘out there’ as the property itself.

Vin Diesel, the most popular man in the world by social media standards, is voicing the team’s largest character and stole hearts with his Iron Giant voice work early on in his career. Zoe Saldana is the queen of sci-fi film franchises and like Oscar nominee Bradley Cooper, can hit any mark on the acting spectrum. Dave Bautista, a long-time pro wrestler is a newcomer to the film acting game but a proven physical force. And last but not least, is Chris Pratt who currently tops a list of most likable stars in the world and is enjoying a career explosion with recent hit The LEGO Movie and upcoming lead role in Jurassic World.

For two years we’ve told you about the five main characters featured in the Guardians of the Galaxy comics, who they were, and what they’re becoming on screen. We’ve shared countless interviews from writer and director James Gunn and Marvel Studios boss Kevin Feige about what the Guardians mean to them and why they are deserving of a big budget film adaptation.

The first trailer for Guardians of the Galaxy released this week (watch our analysis video and check out the HD photos) and while it focused on its leader in Peter Quill aka Star-Lord (Chris Pratt) it smartly found a way to introduce and offer background on its entire roster, without even having them speak a word. Now, let’s let the stars playing these characters briefly tell you about them (along with a few quotes by James Gunn about them told to Total Film).

Chris Pratt is Peter Quill aka Star-Lord

Not a superhero, but cunning and charming

Zoe Saldana is Gamora

A deadly assassin with a heart of gold

“Zoe is about as un-intimidating as you can imagine! She gets in the zone the moment that cameras start filming – but before that she’s basically her loud, brash, completely lovable and goofball self. She got it easy with the makeup – it only took about four hours to put on, whereas it took Dave Bautista and Karen Gillan six hours or more. Zoe and Karen are the two most hardass characters in the movie – they’re our Clint Eastwoods. It should take more than a few people by surprise. “

Dave Bautista is Drax the Destroyer

Lives solely for revenge

Vin Diesel is the voice of Groot

A very strange character

“I love Groot so much I get teary eyed when I think of him sometimes. Essentially, all the Guardians start out the movie as bastards – except Groot. He’s an innocent. He’s a hundred percent deadly and a hundred percent sweet. He’s caught up in Rocket’s life, really. The shot of Groot in the trailer took a few weeks to create, but the development of his look and how he moves took the better part of a year.”

Bradley Cooper is the voice of Rocket Raccoon

Anger issues and the heart of the film

“We’ve recorded most of Bradley’s dialogue already. I suppose you would expect me to tell you he’s fantastic and his characterisation of Rocket will blow your mind – so don’t believe me and just wait to see (or hear) it for yourself. In all truth, we hired Bradley because he’s able to do both comedy and drama – it’s the thing I look for most in the actors on all my films – and to truly sell Rocket – for you to believe a Raccoon can talk (and blow up and shoot tons of stuff) we need a well-rounded actor.”

The Rocket Raccoon video is an important one since it’s the first time we get to hear Bradley Cooper’s voice for the character, which may be a downer for fans who were hoping for a Cockney accent of the character – as featured in some other iterations of him. Still no sample of Vin Diesel voicing Groot however, and uttering his one and only line “I Am Groot.”

According to Diesel, before he was officially cast, he’s also doing motion capture work for Groot but by the time he joined principal photography was complete and most of the visual effects were underway so we’re not sure if he’s doing any physical work for the character.

Watch: Full Guardians of the Galaxy Trailer

Guardians of the Galaxy is directed by James Gunn off of his script co-written by Nicole Perlman. The film stars Chris Pratt, Zoe Saldana, Dave Bautista, Lee Pace, Michael Rooker Karen Gillan, Djimon Hounsou, Benicio del Toro, John C. Reilly, Bradley Cooper, Vin Diesel and Glenn Close.

Captain America: The Winter Soldier hits theaters April 4, 2014, Guardians of the Galaxy on August 1, 2014The Avengers: Age of Ultron on May 1, 2015, Ant-Man on July 17, 2015, and unannounced films for May 6 2016, July 8 2016 and May 5 2017.

Follow Rob on Twitter @rob_keyes for your Marvel movie news!

Sources: Marvel, Total Film