Russia, 1805. Napoleon Bonaparte's French army has invaded Austria, drawing Russia into the war against him. Everyone in aristocratic Russian society is rattled - except hot-headed Pierre Bezukhov (Dano), who admires the French emperor's politics. Pierre is an outcast in society, and the illegitimate son of one of Russia's wealthiest men. But now his father is close to death and his scheming relatives are vying for the old man's fortune - though they expect Pierre to be left with nothing.
Pierre's dearest friend Prince Andrei Bolkonsky (Norton) is excited about war with Napoleon. For him it offers a chance to find purpose in life by fighting on the front line. Unhappily married to a beautiful socialite, Lise (Kate Phillips), he plans to leave her behind at his fierce father's remote country estate and seek military glory for himself. The army under Andrei's wise mentor General Kutuzovexpects a swift victory. But when the French unexpectedly prove their military might, Andrei is thrust into a dangerous battle.
Pierre's other great friend is Natasha Rostova (James) - a beautiful, lively young woman growing up fast and desperate to experience more of the world. When she sees love blossom between her brother Nikolai (Jack Lowdon) and his childhood sweetheart Sonya (Loftus), she is inspired for the first time with romantic thoughts of her own. As the men ride off to war, Natasha and Sonya are left behind to wait and wonder if they will ever return.