Liana and Alexa (Barbie and Teresa) are best friends who share everything, including their love of singing. Upon meeting a girl inside a mirror, the duo embark on a journey that will put their friendship to the ultimate test.
Barbie & the Diamond Castle is a 2008 direct-to-video animated musical film directed by Gino Nichele and produced by Mattel Entertainment with Rainmaker Entertainment. It first premiered on Nickelodeon on September 7, 2008, and it was later released to DVD on September 9, 2008.