Midnight Science Fiction Feature!

Midnight Science Fiction Feature! is the main intro quest in the Fallout: New Vegas add-on Old World Blues.

Quick walkthrough

 * Go to the Mojave Drive-in.
 * Wait until midnight.
 * While the movie is playing, activate the crashed satellite.

Detailed walkthrough
After installing the add-on, you will receive a radio signal from a mysterious broadcast about an invitation to the "Midnight Science Fiction Feature!" in the Mojave Drive-in. After arriving at the Mojave Drive-in, you will notice a crashed satellite in the middle of it. At midnight, the satellite starts projecting a movie (which appears to be a peering eye) on the Mojave Drive-in's screen. Activating the satellite at this point will bring up the prompt window, explaining that you're about to enter a DLC, and won't be able to return until completion. Selecting that you are ready will cause you to be teleported to the Big Empty and start Old World Blues content.

Activating the satellite will bring up a pop-up text box indicating that Old World Blues is intended for couriers of Level 15+ and that you can carry all of your gear to the Big Empty, but you won't be able to return to the Mojave until Old World Blues is completed.

Behind the scenes

 * This is most likely a reference to the Midnight movies of the 1950's, whereas television stations would show low budget horror and science fiction films at midnight.
 * Could possibly be a reference to the Rocky Horror Show's song "Science Fiction, Double Feature".