Looking for some style inspiration for your big night? From Harry Potter to Gossip Girl, we've rounded up the most memorable on-screen prom moments. Who could forget Molly Ringwald's thrift store find in Pretty in Pink, or the dramatic black-and-white look (left) Shannen Doherty wore as Brenda Walsh on 90210? These stars' nights may have been scripted, but that doesn't mean their style can't be imitated in real life! Click through the gallery to find your on-screen prom inspiration!