Barbara is on a trip and Bibi and Bernhard are home alone. Whilst magicking in the mail, Bibi uses the wrong spell. Now all the things from advertisements or letters come out of the mailbox. Among them is a leprechaun who comes out of a letter from Bibi’s cousin Margie. He wants to go straight back to Ireland. And because Bibi takes her time to find the right spell, he causes all kinds of chaos. With a lot of effort and help from Granny Greta, Bibi is finally able to put an end to these turbulent happenings.