Maleficent, a new film starring Angelina Jolie, has a wonderful opening and a wonderful close, but the middle seriously sags. Why that happens speaks to a problem with story structure.
The film opens with Jolie as a mythical creature and a young girl who watches over and protects the Moor, where other creatures like pixies roam. Humans occupy a nearby kingdom. Each mostly keep to their realm until a young man enters the Moor to steal a jewel and is caught by Jolie. They become friends, grow up together, and she falls in love with him.
When the nearby king fails in an attack on the Moor, the young man uses Jolie's love for him to take her wings and get himself appointed king. This sets up a central question, will she get revenge? She curses the new king's daughter so that when she reaches 16, she will fall into a deep sleep that can only be woken from a kiss of true love.
In this middle section, Maleficent watches over the girl, whom she clearly and deeply loves. As the girl gets to know Maleficent, she comes to love her like a mother. But this section of the movie mostly keeps the king scheming to destroy Maleficent off-stage, and there's no real drama around seeing Maleficent care for the girl. Beautifully acted by Jolie, yes; the narrative tension necessary to sustain the movie, no.
Narrative tension is generated when a character has a clear goal accessible to a story's audience, and is blocked from achieving that goal. When an audience has internalized a character achieving that, the narrative tension is transferred to the audience. This is what makes a story compelling.
Maleficent has no narrative tension in its middle section, so the drama of the story sags.
Jolie's wonderful performance can't make up for that.
Jolie as an actress had the same problem in the movie Changeling. Great performance, no narrative tension.
To read some of my longer reviews of popular movies, check out my writing workbook, A Story is a Promise, available on Amazon's Kindle and Barnes and Noble's Nook.