'Men in Black III': First Trailer Reveals Time Travel (Video)

The first trailer for Men in Black III was unveiled online Monday and revealed a major plot twist: Will Smith's Agent J goes time traveling. Or, as noted in the trailer, he goes "time jumping."

The set up is this: Agent J and Tommy Lee Jones' Agent K are going about their usual alien monitoring business when Agent K takes on a side assignment solo.'

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When asked by J what he's investigating, K tells him, "I promised your the secrets of the universe, no more." To which J replies, "Well, what other secrets are there?"

Cut to: J asking Emma Thompson's character Oh to help him located K. A bit surprised, she tells him K has been dead for decades.

And thus comes the time travel element -- Agent J needs to find Agent K in the past.

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Agent J. "time jumps" back to 1969 and lands in an office chair smack down in front of Josh Brolin, who plays the young Agent K.

Men in Black III opens May 25, 2012.