Demons

Elsa and Olaf stand together in an icy chamber, then Elsa's face fills the screen with wide eyes and a shocked expression, followed by a blurry image of a young girl falling through dark water, then a black-and-white scene of a child lying on the ground while another child leans over them, then Elsa appears in a blue dress, running her hands through her hair with a look of distress, and finally turns to face her reflection in a large ice mirror.