Poldark star Luke Norris teases more trouble ahead for Dwight and Caroline in the final series

And Ross himself, played by the estimable Aidan Turner, has had to confront his jealous feelings about Demelza’s admirers, notably Captain McNeil (Henry Garrett) in earlier series and more recently the lovelorn poet Hugh Armitage (Josh Whitehouse).

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But now it seems that Dr Dwight Enys (Luke Norris) and his wife Caroline (Gabriella Wilde) will face an interloper.

“There’s a third wheel who makes things difficult,” Norris told RadioTimes.com at the Radio Times Covers Party. “There’s more turbulence to come.”

He wouldn’t say whether it’s Dwight or Caroline who attracts an admirer. And fans will have to wait until this summer’s expected broadcast of the fifth and final series to find out.

Even those who have read all 12 of Winston Graham’s books will be none the wiser about precisely what is in store.

For the new series, screenwriter Debbie Horsfield is filling in the ten-year gap between Poldark's source texts, book seven (The Angry Tide) and eight (The Stranger from the Sea).

Series four ended the action at the end of book seven with the death of Heida Reed’s Elizabeth, which left her husband George Warleggan bereft.

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In our interview, Luke Norris welcomed the idea of returning to the final five books of the Poldark saga at a later date.

Producer Karen Thrussell said she would like to film the last instalments one day and Norris added it was “a great idea, I would watch it”.

The fifth and final series of Poldark is expected to air on BBC1 in the summer

This article was originally published on 6 February 2019