The book is about a mouse "Tanzmaus Souri", who lives in Australia in the famous Sydney Opera House. On her daily stroll around the Opera House she discovers one day a group of girls in pink dresses. Souri is so nosy and follows them in a large hall of mirrors and barres. Souri is very excited and curious what the girls are going to do.

Children learn about one of the fundamental movement ("plié"), first and second position, structure of class (e.g. warming up, at the barre, ).