Close Encounters of the Third Kind.
Saw it the theater and upon leaving, looked to the sky and wanted to see spaceships like what was in the movie.
An interesting aside was that many years later I belonged to an RC model airplane club aboard Camp Pendleton, CA. We flew off a parade ground/helicopter airstrip. One Saturday morning, we arrived and found six Hughes 500-type helos on the field. All flat black with flat black US insignia. Guarding them was a guy sitting in a Toyota Previa minivan in civilian clothes and wearing jump boots. Also parked nearby was a Ryder box truck.
A little while later, a white commuter Ford van with no markings came roaring up the access road. When it stopped a bunch of other guys in civilian clothes and jump boots piled out. The guy in charge was ranting and raving about all the civilians (us) wandering around 'his' aircraft. Obviously the C.O. of the unit. Someone opened the back of the truck and all their flight gear was hanging from the walls of the box. They all started putting the flight gear on over their civilian clothes in preparation for a training flight.
So, the tie-in is that US government really does hide in plain sight using commercial vehicles, just like they did in Close Encounters.
That, and they really do fly black helicopters with no readily visible markings.