Back at Doc's place, Marty tries to warn him about the Libyans, but Doc is having none of it.
There's also this super-intricate and detailed model of Hill Valley that would normally take a dozen model artists about three weeks to make, but somehow Doc has put this thing together himself in less than one. Maybe he has a second time machine somewhere he's not telling us about?
Anyway, he demonstrates how the lightning thing is going work.
In what is a bit of a stalkerish move, Lorraine has followed Marty to Doc's place, and she…asks him to the dance.