A girl gets invited by a mysterious stranger to go to a store to get a unicorn. She's wanted one her entire life despite the attempts by her zany parents to normalise her.
Sound like a good plot?
It's not, but Brie Larson and Samuel L Jackson manage to pull this off and turn it into a sweet lovely film about life and dreams, and love and growing up.
I think without Jackson and Larson this would have been a ridiculous film that no-one would like, but they made it work and I now forgive Larson for her searingly bad appearance in Kong.