When Thomas (Rhys Wakefield) and his family move to a new home and he has to start at a new school, all he wants is to fit in. When his pregnant mother (Toni Collette) has to take things easy, his father Simon (Erik Thomson) puts him in charge of his autistic older brother Charlie (Luke Ford). Thomas, with the help of his new girlfriend Jackie (Gemma Ward), faces his biggest challenge yet. Charlie's unusual antics take Thomas on an emotional journey that causes his pent-up frustrations about his brother to pour out - in a story that is funny, confronting, and ultimately heart-warming.

The Black Balloon is a story about fitting in, discovering love and accepting your family.