Diesel Dove Into Darkness for 'Riddick' Return

Fast & Furious champ Vin Diesel is bringing his badass sci-fi character Riddick back to the big screen this weekend, and the 46-year-old star tells ET that the most difficult aspect of returning to Riddick was actually not the physical demands of the shoot, but the mental preparation.

"The hardest part about doing the Riddick character is actually not the physical component, it's ... the state of mind that you go into for that character," Vin tells ET. "The preparation for a character like that usually involves many months of being a recluse and being introverted in getting ready for that quintessential lonely anti-hero."

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Following 2000's Pitch Black and 2004's The Chronicles of Riddick, the new Riddick reunites Diesel with director David Twohy for a more pared-down film in which our anti-hero finds himself up against a group of bloodthirsty mercenaries and even more bloodthirsty alien predators. Activating an emergency beacon, he catches the attention of two passing ships – one carrying a new breed of mercenary, and the other captained by a man from Riddick's past.

Battlestar Galactica siren Katee Sackhoff also gets to play a badass mercenary named Dahl in the movie, and she says with a smile, "I absolutely love being physical in movies, even if it's comedy and physical comedy, I absolutely love it. Maybe that comes from being an athlete, I don't know, but I love to run around. ... That's what doing action movies is like -- it's like you feel like a five-year-old again."

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Also co-produced by Diesel, the Riddick cast includes Karl Urban, Bokeem Woodbine, Dave Bautista, Jordi Molla and Matt Nable.