The Phrase: *You Serious Clark?* is appropriately used when someone around you says something so outrageous that you cannot believe they actually just said that.

This phrase was taken from the movie *National Lampoon's: Christmas Vacation*.

Sitting at the table for Christmas dinner, Clark Griswold mentions that he heard a pilot flying over New York spotted Santa Claus, to excite the children about Christmas, but Cousin Eddie found it necessary to respond with *You Serious Clark?*
outlandish claims unbelievable ideas Christmas vacation Christmas vacation
Kayte- I now own Jupiter!
Moira- You serious Clark?
Kayte- Dead serious!

Tom- Will you marry me?
Kayte- You serious Clark?
Tom- Is that a yes?
by VintageStarfish December 6, 2009
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