Watch Sia Perform the 'Finding Dory' Theme 'Unforgettable' on the Ellen Show

Singer/songwriter Sia made an appearance on The Ellen Show and performed the new theme for the upcoming Finding Dory film. The theme song is called "Unforgettable" and Sia was asked to do the song for the film by DeGeneres.

Decked out in one of her famous outfits and wigs, Sia performed with a Dory-blue backlit stage. The music began and Sia performed a new version of "Unforgettable." The song is the perfect track for Finding Dory as Dory is known for having a very short memory.

The jazzy performance was quite elegant and fans can see why DeGeneres tapped Sia for the recording.

Finding Dory is shaping up to be a pretty big film for Disney and Pixar. For the premiere DeGeneres has invited some of her favorite kid talents and most recently her boyfriend Tayt.

Meanwhile, Sia is going on tour for the first time in five years and Miguel will be her opening act.

The tour kicks off in September and DeGeneres publicly thanks Sia and said she couldn't imagine anyone else performing the song.

Finding Dory is set to hit theaters on Friday, June 17. You can watch her performance of "Unforgettable" in the video below.

Watch Sia Perform 'Unforgettable" on The Ellen Show