As Russia prepares for war with France, Prince Andrei Bolkonsky is excited for life on the front line. Meanwhile his friend Pierre Bezukhov is called to his dying father’s bedside.

Andrei and Nikolai prepare for battle with the French, but are they stepping into a trap? In Russia, Pierre struggles to settle into married life with Helene.

Pierre fights a duel that sends his life in a surprising new direction. At the Rostov house, Natasha and Sonya receive unexpected proposals and Nikolai makes a disastrous mistake.

Andrei is in love, but his father is set against him marrying Natasha and insists on a long engagement to keep them apart. Natasha is overjoyed when Andrei proposes but shocked by his decision to delay the wedding and travel abroad for a year. She distracts herself by spending time on the Rostovs' country estate, hunting and getting a taste of Moscow peasant life. But when the time comes to return to Moscow society, temptation crosses her path, and she finds her love for Andrei tested.

Napoleon outrages the Russian emperor by crossing the border and marching his army towards Moscow. In his path stands Prince Bolkonsky's country estate - but the old prince isn't prepared to let the French through without a fight. Marya is shocked to be placed in terrible danger. Nikolai, meanwhile, is stationed far away from the action, but he gets a chance at glory when he crosses paths with a stranger in distress.

Chaos takes hold as Napoleon marches into Moscow and the Rostovs rush to leave the city. As they hurry away, Natasha is astonished to learn the identity of one of her travelling companions and finds she at last has a chance to make amends. Sonya, meanwhile, comes under pressure from the countess to make a great sacrifice for her family.