Cornwall, 1783. Ross Poldark returns from the battlefield to find his father dead.

Rumours spread of a scandalous relationship between Ross and Demelza.

Francis wrongly blames Ross for helping Verity elope with Andrew Blamey.

George expands the Warleggan empire, launching a new ship and bankrupting Carnmore.

Ross prepares for his trial as Demelza and Elizabeth try to help his cause. George does everything in his power to harm Ross, Francis wrestles with his conscience, and Dwight clashes with an entitled heiress, Caroline Penvenen.

As the election leads to rioting, Elizabeth goes to Bodmin herself. Demelza tries to influence the case by making a personal appeal to the judge, but George has a number of tricks up his sleeve as the day of the trial arrives.

Ross and Demelza face financial ruin, and George plans revenge on Jud. Francis, meanwhile, tries to rebuild his life and extends an invitation to Ross and Demelza.

Needing money to open a mine free of George's influence, Ross strikes a deal with a local smuggler. Dwight, meanwhile, tries to diagnose an epidemic and receives help from an anonymous benefactor.

An informant in the smuggling ring poses a serious threat to all, and George buys Ross's debt to finally crush him. Meanwhile, Caroline returns to Cornwall to make an announcement, but it is Elizabeth who reveals a great secret.

Ross tries to help Francis's family financially, but George calls in Ross's debt. Demelza toils loyally to protect all at Nampara, and Dwight and Caroline continue to meet in secret.

Ross joins a smuggling trip in the Isles of Scilly in order to meet Mark Daniel but, in his absence, George moves in on Elizabeth. Caroline convinces Dwight they must elope for a new life in Bath, and Captain McNeil plans to ambush the smugglers on their return.

Ross and Dwight stand trial for their part in the smuggling. A new tin lode gives Ross renewed hope in Wheal Grace, but it is George who is there for Elizabeth when her mother falls ill and deals Ross a bitter blow.

Ross closes Wheal Grace for good. With Elizabeth wrestling with a life-changing decision, Demelza's world has been turned upside down. How will harmony be restored?

Dwight enlists in the navy to forget Caroline, and Demelza visits Verity to spend some time apart from Ross. While Ross considers rejoining his regiment, Elizabeth and George settle into married life, but George's plans provoke the locals to riot.

Sam and Drake provoke Trentishoe and Ross's stubbornness gives George the upper hand. Meanwhile, a great naval battle leaves Dwight's fate in question.

Ross is ordered to leave Roscoff under threat of execution. He travels with Tholly to meet his contact in France, but finds information about Dwight's fate comes at a high price. Sam leads a congregation of methodists in protest outside the church - only to face broken promises from George, who revokes their lease on the meeting house, which leads them to turn to Elizabeth for help. Geoffrey Charles has some words of advice for Drake, who has shared a moment of intimacy on the beach with Morwenna.

George proves merciless as the new magistrate, and Clowance is christened. Ross discovers the means to both help Dwight and combat Cornwall's famine.

Drake finds himself in the Warleggans' firing line as George moves to secure his connection to the nobility, and Ross provides some local aid.

The Poldark family finds itself challenged on all fronts and threatened as never before.

As the Poldarks look to rebuild their marriage and the Enyses to increase their family, Cornwall struggles under the Warleggans, whose power threatens all they hold dear.

Ross faces the challenge of Parliament and the Warleggans refuse to accept defeat. In Cornwall, Demelza contends with a failing mine and fixing Drake's broken heart. Dwight and Caroline welcome a baby daughter. Ossie meanwhile tends to a dying parishioner and George hosts an extravagant party at Trenwith.

Ross is reunited with his family at home, but tragedy strikes in Cornwall. Dwight tells Caroline some devastating news about Sarah. Ossie is seen visiting Rowella by her husband Arthur, who grows suspicious. Emma returns to give Sam her answer, whilst Drake is persuaded into courting Rosina.