Susan and Katherine square off in court in this scene from the Desperate Housewives episode "The Coffee Cup."
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In this great clip, Gabrielle tries to bribe a priest into letting her daughter attend Catholic school. Classic stuff.
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Desperate Housewives Season 6 Episode 8 Quotes

I'm been home-schooling my daughter and it's been a living Hell, so I tried to bribe someone to get her into Catholic school.

Gabrielle

Not only did Susan shoot me at point blank range, she trashed me to all my friends and neighbors.

Katherine