Why THAT Poldark character was the one friend Ross couldn't save

However, while governor of British Honduras, Ned was targeted for his abolitionist views, and wealthy British settlers conspired to land him in trouble in London — and eventually back in prison, sentenced to be hung, drawn and quartered.

In episode six, Poldark (Aidan Turner) launched a daring rescue attempt on the eve of Ned's execution date — only for Ned to back out at the last moment in order to save his friend from a similar fate...

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As Ned was standing with a noose around his neck, a messenger ran onto the scaffolding in a dramatic twist. However, the message was only that Ned's sentence had been reduced by the Prime Minister to just hanging, and he was eventually executed.

"I knew historically that he did die," said Regan of his character, in an exclusive interview with RadioTimes.com, "So [Ned's death] didn’t come as a surprise to me. But I think what might come as a surprise to the viewers who watch Poldark is, I imagine after five series, Poldark manages to save everyone. So I think this is a first where his closest friend dies, because I imagine most viewers will be thinking, ‘Oh that’s alright, Ross will save him at the end’, but unfortunately that’s not the case."

Did Regan predict Ned's change of mind during the attempted prison-break? "No, that came as a real surprise to me, reading episode six."

"But it was great," he added, "it was almost an Eureka moment for Ned, knowing that whatever happened he would always be tracked down and killed, and so it was just a case of him not wanting there to be any collateral damage to the people that he loved.

"Because he knew that Poldark would do anything to keep his friend alive, and it was important that he [Ned] didn’t want Poldark or Demelza and the children and their friends to suffer the same kind of fate that Kitty and Ned had been suffering, which was being hounded by the authorities, and eventually tracked down and killed. I found episode six really moving, actually."

Regan also revealed that he and the series producers decided to give Ned — an Anglo-Irishman who was likely educated in England — an Irish accent "so we could associate the fact that he was an Irishman", and "to make Ned probably a lot more brusque than he actually really was".

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"He’s a bit of a firebrand, he loses his temper a lot, flies off the handle at the first opportunity, he drinks a lot... I think what we wanted to do was to create a parallel character to Ross, who’s a hot-head anyway," he said. "If you turned up the hot-head to a certain level on Ross, you’d end up with Ned. I think that was a deliberate ploy [on the part] of the writer to create that character."

With Ned gone and unrest brewing back in Cornwall, the season is set to end in a dramatic double-bill beginning next week...

The penultimate episode of Poldark season five airs on Sunday 25th August at 8pm and the finale on Monday 26th August at 8:30pm, on BBC1