"Death and All of His Friends" has to be one of the grimmest (and best) episodes of Grey's to date, portraying a horrifying shooting at Seattle Grace. Among many others, both Owen and Derek get shot. In the harrowing season 6 finale, Cristina is really Meredith's rock through and through, forcing her dark and twisty friend to come to her senses in the chaos and even later performing a high-stakes surgery at gunpoint.
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