Would Jones & Brolin Time Travel to the '60s?

Tommy Lee Jones and Josh Brolin play an older and younger version of Agent K in Men in Black 3, in theaters May 25, and Josh said that playing Tommy in the sci-fi comedy was "a little disconcerting at first."

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Josh says that he never actually did his Tommy Lee Jones impression in front of Tommy, and they still haven't even seen the movie together. "Maybe we should create a screening where it's just Tommy and I, and you guys can film it," he jokes. "That would be nerve wracking."

"I think Josh did a good job," says Tommy, choosing not to elaborate. "I thought he played his part in the movie very well."

The long-awaited third installment of the Men in Black franchise finds Agents J (Will Smith) and K (Jones) feeling a little too old to battle unwieldy aliens day in and day out. But when history is somehow rewritten and K ceases to exist, J must travel back in time to put things right, literally diving right into 1969 to team up with a younger version of K (Brolin) to save his partner, the agency, and the future of humankind.

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If Tommy could time travel back to the '60s, would he? "Oh hell no," says Tommy with a laugh. "I don't think there are any good ol' days anywhere. This is the good ol' day. I think we're better now."

"You had really bad TV shows like Mr. Ed and Lost in Space," laughs Josh about the hippie decade. "The '60s was a wild time, man. It all just kind of broke open then."

So, would Tommy do another Men in Black? "Yeah," he replies, matter of fact. "We're gonna start tomorrow, I hope."

Watch ET for more with the stars of Men in Black 3.