"An eerie debut about a little boy who recovers from a mysterious global flu that's killed thousands and inherits an imaginary friend who makes him do violent things... Kids have imaginary friends. Rachel knows this. So when her young son, Billy, miraculously recovers from a horrible flu that has proven fatal for many, she thinks nothing of Delfy, his new invisible friend. After all, her family is healthy and that's all that matters. But soon Delfy...