Playing heroine Sarah Connor in the latest Terminator film required a lot from actress Emilia Clarke. There were all those fights with evil robots, the nail-biting car stunts on the Golden Gate Bridge, and the daily training sessions with "guns, lots of guns, and then some more guns".

One section of the Terminator Genisys script was a particular eyebrow-raiser for the Game Of Thrones actress, however: when she and her co-star Jai Courtney travel through time, completely in the buff.

"I double-checked the age-rating and was like, 'OK, we're good, there's only so much you can see!'" admits the actress, who has also appeared nude as silver-blonde exiled royal Daenerys Targaryen in the hit TV show Game Of Thrones.

"Nude harness time travel, it's an interesting one to add to the CV," she adds. "You've just got to have a sense of humour and laugh. Loudly."

Laughter comes easily to Clarke, who is back to her brunette roots and dressed in a powder blue Dolce & Gabbana dress for our interview. And she reveals that Arnie was game for a giggle on set too.

"He's got really good banter. He had such a calming, gorgeous presence on set that put everyone at ease. And he's such an iconic figure - there were a lot of 'pinch me' moments, when you're like, 'I can't believe I'm actually doing this'."

Schwarzenegger's "I'll be back" line, famously uttered by his robot character in the first Terminator film, was repeated "all the time" on set, she reveals.

"To his face, not to his face, all of it!" confesses the 28-year-old actress, who recalls seeing the violent original while growing up in Berkshire.

"My brother forced me to watch it quite young, so I was a bit traumatised by the apparent ketchup in most of the scenes," she jokes.

"I revisited it as I was getting older, and then in preparation for playing Daenerys, I watched Sarah Connor back, in order to kind of embody some other strong women on screen. So it was funny when this audition came around. I was like, 'Yes, definitely!'"

Set in 2029, Terminator Genisys sees leader of the human resistance John Connor (Jason Clarke) head up the war against machines. He sends Sergeant Kyle Reese (Courtney) back to 1984 to protect his mother - Sarah - and safeguard the future.

Kyle finds himself in a new and unfamiliar version of the past, where he encounters dangerous enemies and unexpected allies, including a new T-800 terminator, the 'Guardian' (Schwarzenegger, this time playing a 'goodie').

We also see flashbacks to Sarah's childhood, during which she was orphaned and placed in the Guardian's care.

"You really get to see how she got to where she is, so there's a reality to her as a character, that hopefully people can relate to," Clarke notes.

Shooting all those action sequences did take its toll.

"I naively went into this not quite realising the full extent of how much stunt work you really do on an action movie. You take it for granted when it's seamlessly put together in a gorgeous movie, but when you're there, you're like, 'Oh, that's the gun, OK that's the hill, brilliant...'

"It was a lot of hard work, but really good for getting into the character of Sarah Connor. To physically put yourself there was very helpful," the star adds.

After graduating from the Drama Centre London in 2009, Clarke appeared in BBC series Doctors and the US made-for-TV movie Triassic Attack, before landing her Game Of Thrones role.

Series five of the often bloody and brutal show recently saw several key cast members culled, but Clarke thinks her character is still safe - "for a minute", at least.

"I'm definitely always on at David and Dan [Benioff and Weiss, the series' creators], saying, 'Can I have the scripts, just to see if I'm alive?' That would be good!"

She dismisses suggestions that the TV show - based on George R. R. Martin's books and known for its graphic violence, sex and nudity - is too close to the bone.

"I think that the essence of the books is placed very firmly in a shocking territory and there are a lot of shocking realities in real life as well. We're just echoing that, really. But ultimately, it's just a story."

Clarke's next project couldn't be further from blood-drenched Game Of Thrones and bullet-splattered Terminator Genisys, however.

Me Before You is the upcoming film adaptation of author Jojo Moyes' novel, about a young carer (Clarke) who forms a bond with the recently-paralysed man she's looking after (played by Hunger Games actor Sam Claflin).

She enjoyed the chance to play a role more rooted in reality.

"I like to stretch myself a much as possible as an actor, and to try as many different things as I can, while I'm in the very fortunate position to be able to do that, and see what shoe fits best, really."

As for another Terminator instalment? "The dot dot dot was there [at the end of the film]," Clarke adds with a smile. "I'm ready to see how that sentence finishes."

:: Terminator Genisys is in cinemas from Thursday, July 2