When a yellow envelope arrives at Hollyhock House addressed to the greatest grandmother in the world, it causes a disturbance among the grandmothers and great-grandmothers living there.

Dot the Diplodocus is puzzled by the strange behavior of her family and friends, but when she investigates she finds a trail of popcorn that leads her to an answer.

It's time for the queen's Grand Ball and everyone in the Kingdom of Klue is invited! Ava and Gabby wear their finest dresses and practice their best manners. Everything is going swimmingly, that is, until the palace is invaded by frogs! How did they all get in? Where are they coming from? Readers in grades 1-4 will help Ava and Gabby put on their thinking crowns to solve the case. Can they unravel the mystery before the guests arrive and the ball...

"Katie's birthday is tomorrow, but she just cannot wait to find out what her present will be, so she and Pedro follow Katie's parents as they go shopping, but none of the places they stop seem present-worthy--Katie is disappointed, but when she gets home a big surprise is waiting for her."