Barney ruins Marshall's bachelor party plans, prompting Marshall to rethink his selection of a best man.
Katherine is unable to keep some of her secrets; Susan's young, attractive cousin reveals more than expected; a surprise wedding ceremony has its share of secrets.
After hearing of possible layoffs at her law firm, Carrie begins to worry about her own job security; Doug loses Deacon's lucky Koosh ball.
Doug, Carrie and Arthur face a chaotic trip to the grocery store on the day before Thanksgiving; Doug encounters a stranger from his past.
Lois runs away from home after her husband forgets her birthday and the boys buy candy instead of a gift.