Sia - Elastic Heart feat. Shia LaBeouf & Maddie Ziegler (Official Video)

Hey! It's that girl, whatshername.... ah! Maddie Ziegler from Lifetime's reality show 'Dance Moms'. She was also in that 'Chandelier' music vid by Sia. 
Now she's back again in a huge bird-like cage with Shia LaBeouf. And love it or hate it, understand it or not, this official music vid called "Elastic Heart" directed by Sia and Daniel Askill, has over 3.5M views already in just one day! Now could someone please explain to us the meaning behind this vid/song?...

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