The Rondo series is a children's fantasy novel trilogy written by Jennifer Rowe under the pen name Emily Rodda.
Things are exacerbated when Mimi, disregarding the rules, makes Leo turn the box five times.
Out steps the evil Blue Queen, who introduces the kingdom of Rondo, the world inside the music box, to the Langlander cousins.
Heartbroken and distressed by the loss of her dog, Mimi takes the 'Key’ and - despite Leo's warnings - enters Rondo.
In the process, they expose several ancient secrets, defeat the Blue Queen, recover Mutt the dog, and discover the real Key; a pendant Mimi inherited from her Great Aunt Bethany.
With that Key, Mimi, Leo and Mutt exchange farewells with their new friends and travel back to their world.
They go on a quest to help find a wizard named Bing with the help of Conker and his talking duck and friend.