Fans got the shock of their lives while walking among the legion of Terminator lookalikes on Hollywood Boulevard -- they ran into the real thing!

Arnold traded classic lines from his 1984 action film back and forth with a "Terminator" lookalike to the delight of tourists walking the Hollywood Walk of Fame. But when he went inside the nearby Madame Tussauds posing as a wax statue, he really got heartbeats racing.

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"He looks real," said one fan before scampering out of the room when Arnold broke his pose.

The prank was done to spread the word about a contest on Omaze.com to win a chance to attend the Hollywood premiere of "Terminator Genysis."

In the movie, a fractured timeline is created when the leader of the human resistance, John Connor (Jason Clarke), sends Sgt. Kyle Reese (Jai Courtney) back to 1984 to protect Sarah Connor (Emilia Clarke) and safeguard the future. This causes Sgt. Kyle Reese to find himself in an alternate version of the past with unlikely allies, including the Guardian (Schwarzenegger), dangerous enemies and a new mission to reset the future.

"Terminator Genysis" hits theaters July 1.

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