Shadow Conspiracy (movie, 1997)

Bobby Bishop is a special assistant to the President of the United States. Accidentally, he meets his friend professor Pochenko on the street. Pochenko has time to tell Bishop about some conspiracy in the White House but then immediately gets killed by an assassin. Now bad guys are after Bobby as the only man who knows about a plot. Bishop must now not only survive, but to stop the conspirators from achieving their goal. And he doesn't know whom to trust.