David callaway tries to piece together his life in the wake of his wife's suicide and has been left to raise his nine-year-old daughter, emily on his own. david is at first amused to discover that emily has created an imaginary friend named 'charlie', but it isn't long before 'charlie' develops a sinister and violent side, and as david struggles with his daughter's growing emotional problems, he comes to the frightening realisation that 'charlie' isn't just a figment of emily's imagination.