For your amusement, we present one of the unaired pilots for Buffy the Vampire Slayer. There are apparently two floating around; we’ve been told this is the second, later one. Both feature most of the right cast, with two major exceptions: Principal Flutie is played by Stephen Tobolowsky (“Ned Ryerson” from Groundhog Day) instead of Ken Lerner (Star Trek actor Armin Shimerman doesn’t take over as Principal Snyder until the 9th episode), but the biggie is that Willow isn’t Alyson Hannigan.
You can tell Joss wrote this, but the snappy dialog associated with the show (and with Angel and Firefly) apparently developed after it got picked up.