The plot is basically just a boy riding alone on a monorail(?) type of train. (I remember it being an elevated track.) He was reading a Marvel Star Wars comic, and his imagination cuts loose as the train keeps going. A whole lot of pseudo-2001 visuals set to a synthesizer score follow, as the boy imagines travelling in hyperspace and firing at the bad guys.
There is no dialogue, which is why it might have seemed like it was a music video.
When he arrives at his station, Vader is waiting for him! He starts to flee, when Vader grabs him! The boy snaps out of the fantasy, and realizes it's just his older sister. They go down the escalator together. The End.
I wish I could recall the title. It's been too long!
