I know a guy who told his sister that he couldn't believe he had seen her on national TV (at a baseball game) picking her nose. He was embarrassed for her and the family. He seldom joked, so she bought in and stayed up half the night playing the game back frame by frame. She and her nose were never on camera. So she plotted.
Months later, she casually threw out the idea that I might have some relatives coming the next summer from Europe. A month after that, she went into more detail. The visitors were young, female, and would be traveling across the southern tier of states, coast to coast. (He was young, single, and living in Las Cruces at the time.)
She let the idea simmer for a dozen weeks, then said they were definitely coming, had sent pictures of two very pretty adventurous girls, and that they would like to meet if schedules could be adjusted.
Just a week into March, she told him the girls were coming at the end of the month, and work being what it was, nobody was able to drive down to meet them on the only day they would be traveling through. She told her brother that she had given the girls his number, and would he mind just taking them out to dinner or show them around for an afternoon?
He called his mother and complained that his sister would share his number with strangers, and expect him to entertain them. But, of course, he didn't turn the phone off.
Then the sister did the most bizarre thing. She got her friend to fake a Dutch accent (who knows what that really sounds like?), and call her brother. I heard the call. It was the worst performance I've ever seen. Botched completely. A conglomeration of Jamaican, French, and English English. She giggled the whole time, which, combined with his willing naivete, allowed her to pull it off, amazingly. Oh, and by the way, she managed to arrange a two night stay in his apartment to recharge from their travels.
The brother spent the next days thoroughly cleaning his digs, stocking his fridge, and even bought a shirt. His roommate, who had a girlfriend, vacated.
Exhausted on the day the visit was arranged, he again called his mother to complain. "I haven't heard a word from anybody up North offering to help out with a little cash. I can't believe they are just dumping these people on me for the whole weekend!"
His mother, who was not in on the joke, but knew her children, asked, "I know, I know, but... What day is this?"
"It's Saturday! And I've got two midterms THIS WEEK!"
Patiently, "Yes, but, what is the date?"
"It's April firs...", then moaning, "APRIL FIRST!! She WOULDN'T! REALLY?? Aw fer cryin'...", and he hung up.
The sister didn't answer her phone that day, but her brother received a message - Happy April 1st! Payback, Nosepicker.
When they next got together, it was as if nothing had happened.