2U David Guetta Feat. Justin Bieber
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Music Video Freeze Frames: The Most Memorable Scenes
Undoubtedly one of Katy's most memorable videos, the scene from 'Last Friday Night (T.G.I.F.)' that stands out most is the first time we see the 'California Gurls' star in full costume as her nerdy 13 year-old alter ego Katy Beth Terry.