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Season 1 - Sep. 19, 2007
Season 2 - Sep. 01, 2008
Season 3 - Sep. 14, 2009
Season 4 - Sep. 13, 2010
Season 5 - Sep. 26, 2011
Season 6 - Oct. 07, 2012

Gossip Girl Season 4 Episode 19
HD
Overview:
Serena enlists Charlie to go undercover Gossip Girl-style to determine why Dan and Blair are spending so much time together, and what role an unexpected visitor is playing in their lives. With Nate