To 'pull a Hagelmoser' is a (roughly translated) traditional, slightly-out-of-fashion German idiom describing a young, dopey person attempting to attend a festivity that already took place a day ago, thus causing amusement witht the irritated hosts who are suprised by the late arrival.
Fritz, what are you doing here? Uncle Hubert's divorce dinner-party was yesterday! You've obviously pulled a Hagelmoser.

Let me check my calendar for your sister's wedding ceremony. I certainly don't want to pull a Hagelmoser.
by Guenther-San July 15, 2010
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