The navigator first caught her eye after he was rescued from a prison cell in France by her husband Ross (played by Aidan Turner) and has been slowly seducing her with poetry and drawings.
"I think Demelza just feels honoured by the attention – no one has ever written her poetry before," actress Eleanor Tomlinson, who plays the stubborn Beauty, told Radio Times.
In the final instalment, Hugh (Josh Whitehouse), whose eyesight is still recovering, will ask Demelza if she will grant him a "taste of heaven" before he "goes into the darkness".
The 25-year-old appeared to confirm that her character would cheat on husband Ross with the charming soldier.Related articles
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"Demelza loves Ross, but she doesn't need him to the extent that she once did," she explained.
"I think that this relationship