11-year-old Nelly has a heart as big as a balloon, and nerves as strong as steel ropes. After all, she is a nanny, a nanny for monsters. And very popular, too! Tonight Nellie will have to look after the monsters from house No. 55. The girl is always attentive to her charges. She is ready to help with the choice of wallpaper (sticky or hairy?) and with the purchase of alligator fillets (for pet babak, of course!). And everything was going great until the farmhand named Gluck (and it was him who Nellie had to look after this time) ran away! So, it’s time to call your faithful monster friends for help and go on a search!