Marvel kicks off its Phase II sequels this summer with Iron Man 3 in May, followed by Thor: The Dark World in November. Actress Jaimie Alexander, who returns as Sif in this Thor sequel, recently spoke out about the follow-up, revealing it has a darker tone.

"It's going to have a bit of a darker feel, a lot more action. We get to explore different realms a lot more, and you get to see a lot more of Asgard. You get to know the people of Asgard."

The actress also revealed that the relationship between Sif and Chris Hemsworth's Thor will be explored.

"We sort of explore the Sif/Thor relationship a little bit. It's more getting a feel of who these people are and how they are the way they are with each other. It was fun for me, and fun for Chris (Hemsworth). Him and I are almost like brother-sister types, so I was like, maybe that translates into 'They love each other' on camera. It's a little weird."

She also spoke about going into the vibe of this sequel, with a new director, Game of Thrones' Alan Taylor, at the wheel.

"That was hard, at first. I didn't know what to expect. I love (Thor director Kenneth Branagh) very much, and he is a huge staple in my life because he launched my career. I have to say, though, it's always great to work with new people, and Alan Taylor has brought a whole new vision to Thor. We've remained our own characters, obviously, so there's still that similarity between the first and the second one, but there's a darker feel to this one. A little bit more gladiator-ish, a little bit more Viking-ish. I'm really excited to see how it turns out."