Amy is a teenager with cerebral palsy from birth. Her difficult life doesn't stop her from pursuing independence, but due to loneliness and her growing willingness to become vulnerable, she accepts help from a teen with problems of his own. Matthew is neurotic and obsessive, symptoms of his lifelong battle with OCD. One day, he confronts Amy for being so difficult to help, and Amy accepts him as a tutor and helper.
The two discover that their lives of chronic health issues make them similar in important ways. They understand each other emotionally in a way most people never will—they know what it's like to have a unique burden in life, and even though Matthew's issues are mental, Amy understands many of his frustrations. Their friendship can't exist on an island, however, so Amy tries to make friends. Her attempts fall flat, not because people dislike her, necessarily, but because people their age don't have the patience to wait for her messages to come through the talk box she uses to communicate.
Matthew's problems aren't simple either. His neurotic ritual obsession over the tiniest details make his every day life more arduous and anxious than his peers can even imagine. The only person who knows what it's like to be limited in an uphill, tedious life is Amy herself. As their time together continues, they suddenly realize how important it was to have someone alongside who understands things, and slowly, they realize that they've fallen in love.