U.N.C.L.E.: The phone at the end of the level says 'U.N.C.L.E.', which is referencing 'The Man from U.N.C.L.E.', another spy show from the sixties. This is a reference to the intro of 'Get Smart', a classic spy show. Get Smart: Near the end of the level, there is a series of doors that lead to a phone.

This is a reference to Roger Moore and the James Bond movie 'Goldfinger'. Moger Roore: In the barracks, there is a magazine next to the TV that says 'Moger Roore' and has a gold ring on it. A reference to the TV series 'The Avengers'. STEED: In the briefing room, there is a coat hangar with the name STEED and has an umbrella and a hat. Burning fuse: The burning fuse can be seen on the two screens in the red key room which is a reference to the '66 show 'Mission: Impossible'. Mission Impossible: The computer room (and everything in it, including the knife) is a reference to the movie 'Mission: Impossible'. THIS TAPE WILL SELFDESTRUCT: In the beginning, a tape deck will play a message and selfdestruct. These are the Easter Eggs found in Duke 3D's Episode 4:

Duke nukem easter eggs