Julia Louis-Dreyfus got her teeth into the action in 'Thunderbolts'.The 63-year-old star returns as the devious Valentina Allegra de Fontaine in the forthcoming Marvel Cinematic Universe (MCU) movie and explained that her alter ego isn't afraid to get her hands dirty in the film.Julia told Entertainment Weekly at San Diego Comic-Con: "In this film, she certainly takes advantage of people we've come to think of as underdogs and uses that to her advantage."It was fun for me to play a hyper-manipulative person who is about four steps ahead of everyone in the piece, and that was cool. And I did my share of kicking ass."Geraldine Viswanathan makes her MCU debut as de Fontaine's assistant Mel and described it as a "dream" to be working so closely with the 'Veep' star.The Australian actress said: "I'm kind of her little right-hand man. And kind of going,...