Poldark fans will see how Demelza is unable to resist the charms of aristocrat Hugh Armitage in the new series.
“He pays Demelza some attention, which is nice,” actress Eleanor Tomlinson, who plays Demelza told The Sun.
“I’m not going to give anything away but I’m intrigued to see how the fans respond to it,” she said.
Handsome newcomer Hugh is played by actor and Burberry model Josh Whitehouse, 27.
Series three begins with Ross, played by Irish actor Aidan Turner, 33, and Demelza back together – after they were reunited at the end of the last series.
“In series two we left Ross and Demelza in a bit of a pickle with Elizabeth being pregnant – potentially with Ross’s baby,” said Eleanor.
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“So there’s lots of twists and turns in this series.”
The series has turned Aidan into a heartthrob. “He’s such a lovely person,” says Eleanor.
“I think he’s a bit shy and finds it all a bit embarrassing.
“What’s great about Aidan is that he’s such a brilliant actor.”
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She has laughed about the awkwardness of filming sex scenes together.
“They say it’s a closed set, but there’s still 25 people standing around while you’re in just a beige bra!” she said.
Eleanor has explained why she thinks people like watching Eleanor and Ross.
“People can relate to their relationship,” she has said. “It’s a realistic relationship, so people root for them to make it work.”