Elizabeth obtains a tonic designed to induce an early labour, hoping to persuade George that Valentine is his child once and for all – but the Warleggans’ rift is plain as they return to Cornwall. Ross returns to Cornwall to mend things with Demelza, realising he killed Adderley because he could not kill Hugh.
Morwenna seeks out Drake and this time Elizabeth does not seek to intervene – but when George returns home to find Morwenna with Elizabeth in Trenwith, he banishes Morwenna from the estate.
Spurred by George’s ferocity, Elizabeth takes her potion and a painful labour commences. Dwight is on hand, but when Ross hears of Elizabeth’s continuing ailment he rides immediately to Trenwith…
The Poldarks, Enyses and Warleggans enjoy London’s distractions. George dotes on Elizabeth, delighting at the prospect of an heir and announcing plans to host a charity ball, but their domestic bliss soon comesunder threat. At the Warleggan ball Adderley takes a fancy to Demelza, betting George he’ll cuckold Ross within a month, which gives rise to deadly complications.
After it is revealed that Nathaniel Pearce embezzled Pascoe’s client’s funds, the Warleggans take action. In London, Ross finds Geoffrey Charles led astray by Adderley. Sam convinces Drake to return from exile following his abandonment of Rosina and Morwenna’s subsequent rejection and Morwenna reveals some news. Dwight meanwhile helps in the development of Truro’s infirmary.
George increases the strain on the struggling poor, driving Ross to make a risky gambit. The adversity the Poldarks face, however, may not be confined to Cornwall alone.
While George furthers his return to Westminster, Ross is reunited with his family at home. Tragedy strikes in Cornwall, however, forcing him from the quiet life into action again.
Ross makes his maiden speech in parliament and finds himself a little notoriety in London where he also reunites with a now adolescent Geoffrey Charles. In Cornwall, Demelza contends with a failing mine and fixing Drake’s broken heart. Dwight and Caroline welcome a baby daughter, Sarah, into the world but Dwight’s happiness is short-lived as he makes a disturbing diagnosis. Ossie meanwhile tends to a dying parishioner, Nathaniel Pearce, who confesses to losing his clients’ money on bad investments, money secured in Pascoe’s bank. He takes the information to the Warleggans in the hope of selling the information. George hosts an extravagant party at Trenwith in the hope of buying his way back into Parliament via purchasing a borough. His new friend, the dangerous socialite Monk Adderley, makes the necessary introductions to set George on his way.
Episode 2 – The Poldarks determine to get their relationship back on track and the Enyses announce they’re with child.
Hugh’s worsening health threatens his chance to stand in the election however, and the prospect of him remaining in Cornwall adds pressure to the Poldark’s fragile marriage. At the Sawle Feast, Tom Harry challenges Sam to a wrestling match. When Emma offers herself as the prize, Sam accepts.
To everyone’s horror Hugh continues to worsen and remains unfit to stand in the election. Falmouth offers the candidacy to Ross but will he accept?
A corn riot erupts in Truro, and Zacky’s son Jago leads the charge. Sam Carne and Drake Carne attempt to dissuade him but arrive too late, and a merchant is killed in the fighting. Tom Harry tells George that the Carnes and Jago murdered the man, and Ross finds himself powerless to save his brothers-in-law…
The Poldark family finds itself challenged on all fronts and threatened as never before.
Series 3, Episode 8 – Ross is adamant George will lose in the election and determines to get a headstone made for Agatha’s grave, something Trenwith has neglected. George, meanwhile, questions Dwight over Valentine’s legitimacy and – paranoid and jealous – shuts himself to Elizabeth, as Rowella begins to seduce Osborne Whitworth and Demelza receives tokens of Hugh’s affection. Sam continues to pine after Emma, as Dwight instructs Osborne to forego intercourse with Morwenna and Cary informs Lord Falmouth that the Warleggans will be opposing Falmouth in the election. Ross returns from his mine to discover Hugh Armitage at Nampara with Demelza – and this time Hugh’s attention does not go unnoticed.