Close Encounters of the Third Kind.
I never watched it when it came out. Or when it was expaned. Or when it aired repeatedly on cable, etc etc.
Caught it at a museum screening recently.
Then or now I do not understand the fuss. It does become apparent that Spielberg has been ripping himself off ever since (the famous "water ripple" scene in Jurassic Park also can be found in Close Encounters, but it didn't make a ripple in pop cultural references then).
Yes, and Star Wars. Okay, I'm not a fan but I know lots of people who did like the Star Wars movies.