After the war for the American colonies, Ross Poldark returns home to Britain — to his family estate in Cornwall, where his parents once owned copper mines. He’s grown weary of military life, which he was forced into for three long years after being caught smuggling. But what awaits him at home is disappointment. No one is expecting Poldark — his father has died, the copper is long gone, and his beloved Elizabeth is now promised to another man. The family estate lies in ruins.
With nowhere else to go, Ross decides to rebuild the mine and restart copper production. It proves far from easy: another man has already laid claim to the land, and the miners have all scattered. One day, Poldark rescues a young woman named Demelza, takes her in as a kitchen maid, and eventually marries her. After gathering a new team of miners, he manages to get the copper operations running again — but new challenges arise. The copper vein remains elusive, forcing Ross to reconnect with smugglers, putting both his freedom and his life at risk.
Meanwhile, his social standing begins to crumble, and his lingering feelings for Elizabeth strain his marriage to Demelza. Pushed to the edge, Poldark makes a desperate decision — to join the newly erupted war between England and France.