The Waverly Ring Affair The Man from U.N.C.L.E. : Season 2 Episode 19

When secret "File 40" documents turn up outside headquarters, Waverly assigns Solo and Illya to find out if George Donnell is a double agent. Carla Drosten is too anxious to accuse Donnell and Solo must use special "Waverly rings" to try and expose the real double agent.