Geronimo's sister Thea narrates this adventure packed with mystery and friendship! The Thea Sisters are headed to Italy for a ballet competition! But the mouselets aren't just there to dance -- they are there to investigate. A group is plotting to rig the prestigious contest, and the future of the mouselets' new friend -- an aspiring ballerina -- is at stake! Can the Thea Sisters stop this scheme before it's too late? 这个故事讲述了老鼠记者杰罗尼莫的妹妹西娅的一次充满神秘和友谊的冒险！ 西娅和姐妹们一同前往意大利的一个芭蕾舞比赛！但她们不只是去那里跳舞而已——她们其实是去进行一次秘密的调查。一伙不法之徒正在密谋操纵这场重要的比赛，她们的新朋友——一个心中充满抱负一心渴望成为芭蕾舞演员的老鼠——危在旦夕！西娅和姐妹们能成功阻止这场不幸的发生吗？