Katy Perry Geeks out in 'Last Friday Night'

Rebecca Black guest stars in goofy video for 'Last Friday Night'

The best and weirdest thing about Katy Perry's video for "Last Friday Night (T.G.I.F.)" is that it's simultaneously nostalgic for the late Eighties and, like, ten minutes ago. The lyrics are very of-the-moment, with references to "epic fails" and embarrassing party photos ending up online, and the video leans hard on goofy Eighties imagery, but the clip is at its best when both time periods collide and coexist without explanation. The most charming bit happens about halfway through, when viral pop sensation Rebecca Black turns up to give Perry a makeover that essentially transforms her from female Steve Urkel to a brunette Kelly Bundy.