Molly, Fiona, Sam, and Lauren are part of a mildly successful wizard rock band called The Brixton Banshees. As they begin to grapple with the ending of the Harry Potter franchise and what their lives will look like after high school, their friendships are tested. Full of heart and pop punk, The Brixton Banshees is a love letter to fandom and the works made within it, especially by nerdy teenage girls.