Poldark star Aidan Turner was injured by a freak wave while filming the drama.
The second series of Poldark starts next weekend, after its debut season was a huge and unexpected hit for the BBC.
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But Aidan has revealed that he was hurt and even dropped Eleanor Tomlinson, who plays Demelza, in the sea off the Cornish coast during filming, after a wave slammed a boat into his head.
The heart-throb told Radio Times magazine: "There's nothing like the Cornish sea at the height of winter for putting you in your place.
"We were filming me lifting Demelza out of a boat in the actual sea when this huge wave picked up the boat and slammed it into my head.
"I dropped her in the water – not very Ross Poldark," he said of his romantic hero alter-ego.
"And nobody was coming to see if I'm OK. I was the man injured..."
But Aidan said he was not the only member of the cast and crew who was hurt in the incident.
"One of the underwater cameramen got cracked as well and he was concussed.
"These waves, you wouldn't think there's anything to them, but once you get out there you're at the mercy of Mother Nature and she doesn't care how well the previous season rated," he said.
Poldark returns on Sunday night when it goes head to head with Victoria, ITV's rival period drama starring Jenna Coleman.
The finale of the first series last year saw Poldark arrested for murder and plundering a shipwreck and his wife Demelza left alone on the Cornish cliff-top.
In the new series Ross faces capital crimes while he and Demelza are still dealing with the death of their daughter, Julia.
Aidan told the magazine: "You'd think at the end of season one it can't get any worse for these guys.
"Ross's company's bankrupt, they're completely broke and they've just lost their child.
"But it just slowly does get worse ...There's prison ... all sorts. But Ross is more comfortable when he doesn't share with anybody, he just takes the burden and the responsibility all himself."
Aidan said that despite filming in the heart of winter on freezing Cornish beaches, he tried to keep a smile on his face.
"The lead actors on any show end up setting the energy level, and if somebody is grumpy, it's hard to get the crew going.
"So no matter how cold it is, you just have to man up and get on with it."
Aidan, whose shirtless scything in the first series turned him into a sex symbol, said of his rise to fame: "I hate having anyone saying I'm blowing up – it makes me sound like Veruca Salt, rolling around going blue.
"Everything feels like a slow progression."