Brian Williams met Edward J. Snowden in the Kempinski Hotel in Moscow last week after months of negotiations between NBC News and intermediaries for Mr. Snowden.

The conversation, which lasted more than four hours, will air during a special report on NBC Wednesday night at 10 p.m. It is the first interview Mr. Snowden has granted to an American television news organization since he emerged as the central figure in the revelations of surreptitious collection of information, on both domestic and international figures, by the National Security Agency.

In an interview, Mr. Williams said, “What’s going to be most interesting is to see if it moves the conversation or changes any minds.”

As Mr. Williams described it, the back story of the interview contained its own quotient of cloak-and-dagger activity, including unannounced plane travel, lost luggage, hotel bookings under assumed names and two days sequestered in a room with a view of Red Square.