Set in the buzzing city of Johannesburg, 'Opus' follows a day in the life of Lebo, a young aspiring bassist living in the informal settlements. After losing his parents and inheriting the double bass instrument 'Bontle', Lebo has developed a symbiotic relationship with his 'Bontle' and his music, which have made him an outsider in the community, but have become his anchor for getting him through his poverty-stricken life and the harsh city landscape.