Dartmoor,1914: To his wife(Emily Watson)'s dismay farmer Narracott(Peter Mullan) buys a thoroughbred horse rather than a plough animal but his teenaged son Albert(Jeremy Irvine) trains the horse and calls him Joey,the two becoming inseparable. When his harvest fails the farmer has to sell Joey to the British cavalry and he is shipped to France where,after a disastrous offensive he is captured by the Germans and changes hands twice more before he is found,caught in the barbed wire in No Man's Land four years later and freed,due to a bizarre truce. He is returned behind British lines where Albert,now a private,has been temporarily blinded by gas but still recognises his beloved Joey. However as the Armistice is declared Joey is set to be auctioned off. After all they have been through will Albert and Joey return home together?