The drama, written, directed and produced by the 12 Years a Slave filmmaker, features an all-star cast including Saoirse Ronan, Paul Weller, Stephen Graham, Harris Dickinson and Kathy Burke. The film follows the epic journey of George, played by newcomer Elliott Heffernan, who is sent to the English countryside for safety during World War II. He embarks on an adventure to return home to his mother Rita (Ronan) and grandfather Gerald (Weller) and finds himself in immerse peril, while Rita goes on the search for her missing son.