Eraser (1996)

It's Federal Marshal John Kruger's duty to keep witnesses hidden within the government's Witness Protection Program safe. Now he must protect Lee Cullen, who inadvertently uncovered a scheme to deliver one of the most advanced super-weapons ever developed--the rail gun--into hands that could shift the world's balance of power forever. What she doesn't know is that the conspiracy reaches the highest levels of government and industry, and the players involved will stop at nothing to keep her from exposing the truth. Kruger is matched against an unknown challenger whose cunning skill equals his own as he guards Lee against the conspirators. As Kruger himself falls under suspicion as the traitor within the program, he sets out to prove his innocence to Robert Deguerin, his mentor, and Beller, the head of the WPP. In a world where allies could be enemies, Kruger and Lee come to trust only each other as the deadly players in the conspiracy close in on them, and time continues to run out.