Bewitched

Up to this point in the series, generally Endora's spells have been on objects associated with Darrin, such as a statue, a watch, a bowl of popcorn, etc. With this episode, Endora's spells are placed directly on Darrin, causing him to perform different sorts of exaggerated behavior (e.g. too cheap, too vain or too snobbish) or to have everyone react to him in the same way (e.g. hating everything he says or loving his ideas even when they're terrible). This plot device will arguably become the most overused one in the entire series.