 At the age of nine, Barclay played Hamlet in a school production and decided to become an actress.At the age of 13, she got herself an agent, and supported herself between TV movies by working in a video store.Diana Rowan (the same casting agent who discovered Anna Paquin, as nd Keisha Castle-Hughes) discovered Barclay in a school play and cast her as Celia in 2004's "In My Father's Den", that rose the actress to prominence.