Kit Harington had never heard of his 'Eternals' character before being cast in the superhero movie.

The 34-year-old actor stars as Dane Whitman/Black Knight in the new Marvel Cinematic Universe (MCU) blockbuster and admits that he didn't know much about his alter ego, although he was attracted to the part by the "essence of the character".

Asked if he was familiar with the character prior to the film, Kit told Variety: "No. If I'm totally honest, I hadn't heard of the character.

"I had to sort of read up on him and just see what the basics were. But the essence of the character and his powers seem to me very interesting."

Kit admits that he has no idea where Marvel will take the character but was grateful for a superhero with "meat to get into".

The former 'Game of Thrones' star said: "God knows where it's gonna go. So I don't know, I can't predict whether, where, if anywhere, they'll take the character. But the basics of him having something that seems to be cursed, I thought, had a lot of meat to get into."

The movie is Kit's first major project since 'Game of Thrones' – where he played the role of Jon Snow – came to an end and the actor had no qualms about jumping from one giant franchise to another.

He explained: "I don't think you get to choose when these things come along. Like, if Marvel calls up, and they say, we've got this interesting character for you, would you be interested in being in this movie...?

"I mean, my process was it'd been about a year and a half since I'd filmed 'Thrones'. It seemed like an interesting character and an amazing universe, and that seemed like a no-brainer to me."

Kit continued: "I've got nothing against possibly long-running franchises and being in them. They've done very well for me! I've really enjoyed it. So it wasn't a very difficult decision to make.

"Once I saw what they were planning with this – the director, it's Marvel, the character's cool – it was a pretty easy decision."