Kenneth Branagh is an international star of stage and screen who's as adept at performing Mamet or Stoppard on stage as he is at directing a summer blockbuster like "Thor." In "My Week with Marilyn," Branagh takes on the role of Sir Laurence Olivier, the legendary thespian who directed and starred in "The Prince and the Showgirl" with Marilyn Monroe. It's this production that's at the heart of "Marilyn," as the actress, played by Michelle Williams, struggles with the staid British set, the pressures of working with Olivier and her ongoing personal drama.

So, what's the Shakespeare-trained actor like in person? Branagh's as charming as one would hope, easily chatting about playing the legendary Olivier, the trials and tribulations of directing, and his lifelong love of "Dr. Who."

With you playing Olivier, there's a rabbit hole that you're falling into of the director and the actor who played Hamlet, and so on. Was that synchronicity, or were you like, "Yes! Finally!"

It became part of the attraction after the initial thing of thinking, "Well, is this the right thing for me to do?" but then being won over by the screenplay, by my colleagues -- David Parfitt producing, who's a great friend, and Simon Curtis, whom I worked with before but not as a director ...

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I was directing "Thor" at the same time, so the idea of being a director becoming an actor who was going to play an actor who was directing a film in which he's acting, and for that qualification, me being a director who acts in films that he's directed -- I loved the extra layers of that. I knew that I would have rare experience of all of it, and some of it happening even as we spoke, because there was some nights when I would go from finishing shooting "My Week with Marilyn" ... and instead of sitting with Eddie Redmayne [who played assistant director Colin Clark] in a fictional screening room looking at a pretend Marilyn Monroe, I would go to a real screening room as a real director looking at our pretend rushes for "Thor."

Everything about it was like a Magritte painting or something. You know, you looked in the mirror and you saw many different layers of the same image around in your life.

Did you ever slip up and go into "My Week with Marilyn" and say, "I need more Dutch angles!" like in "Thor"?

[laughs] I made a bit of a rule with my Marvel family. I couldn't do anything at lunchtimes ... The process of becoming Sir Laurence was almost a kind of a regular ritual. In the dark, in the early morning of the autumn of winter in England at Pinewood, I would arrive outside that same sound stage and there would be Michelle. She'd just be taking a breath before we'd head into the makeup caravan, and we'd stand there for a few minutes and we'd have a natter, always about something banal, about the weather, what did you watch on the telly last night, something like that.

Then we'd both take a breath, and she'd go down to her end of the makeup caravan, and I'd be at this end, and it'd be three people around me with a prosthetic chin, which I was going to put on to give me Olivier's cleft chin and take away my spots and give me a bottom lip, and on the other end, Michelle would start the Marilyn transformation.

Then I'd put my headphones on, and I would listen to Sir Laurence Olivier reading the Bible. He [did] an entire dramatic reading of the Bible, quite an extraordinary vocal performance, and this would take a couple of hours while all that went on. And I would close my eyes, and when I'd open my eyes again, the dye was in the hair, the pomade was in the hair, the savage parting was there, the chin was there, the arched eyebrows had been plucked and redone and colored and everything, and I'd start to see him.

At one point, as Olivier, you say that directing is the most wonderful job in the world; and, to paraphrase, Marilyn makes you never want to direct again. Have you ever had those moments in real life with directing your own movies?

I'd have some challenging moments, yes, where the process for some people is so sort of tunnel-visioned, is so necessarily selfish and sometimes destructive to those around that it is hard to communicate, it's hard sometimes to always wonder if it's entirely worth it ... What happens is that with difficult processes on a film, they get very intensely compressed because a clock is ticking. There's a budget and there's a producer, and basically, as a director, with almost the worst behavior, you've just got to suck it up because on the whole, the studio's not going to say, "Okay, we'll reshoot it. Fire that person and just reshoot it." They're gonna say, "Tough, get on with it. So they're difficult; so what?"

But there have been some very tricky individuals to deal with, though some made me understand as I looked at the script [for "Marilyn"] the kind of fatigue of dealing at this high level of temper, this high anxiety level. Meeting people whose nerve endings are very exposed, who are often very frightened, who understand -- they come on the set sometimes, particularly people in leading roles, they come on the set with the feeling of pressure that can be sometimes carrying a movie. You don't get many goes -- you could be the biggest star in the world, but you have two, three flops, and life changes significantly. Carrying a movie is both a great privilege, it's a great opportunity, but it can be a great pressure, and sometimes that can make people behave very oddly.

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With "Thor 2," one would assume the relationship was amicable since you're still a producer, but could you shed any light on why you're not doing the sequel?

Timing. I came here today from Copenhagen. I'm in Sweden shooting another series of "Wallander," which I had been committed to, and I did a play in Belfast just a little while ago, and so the timing of both that work and then the need to get back immediately into the forging of "Thor 2" just made it not an option for me. So it was amicable, and they understood and it had been nearly three years of working [on "Thor"], much longer than we'd originally envisaged, very pleasurably from my point of view, but I had these other things that I wanted to do.

I felt a great privilege at doing a movie like that, but whether it's Shakespeare or other things, I don't feel proprietorial about these things. I think I was very privileged to be part of something that was also very much part of other people's work as well, so I'm thrilled -- listen, I'm thrilled beyond measure that a second movie's being made, and I love [Chris] Hemsworth and all the actors in it, [Tom] Hiddleston, and would happily make a movie with the Marvel team again in a heartbeat, but timing on this one wasn't right. And in the end, I think they have a chance to go into the second one with a kind of excitement and innovation with the choice of Patty Jenkins, who I think is a fantastic choice to direct the movie. So I'm very excited about that. It just worked out the way it was meant to work out.

I understand you're a big fan of "Dr. Who," and I was wondering if they had approached you to write a guest episode, perhaps, or even do a cameo.

Not thus far, though, but what a fun prospect that would be. I go all the way back to the very first "Dr. Who," I really do, from the very first "Dr. Who." It was an actor called William Hartnell, and I remember from my time in Belfast when I really was quite young, hiding behind the sofa when the slightly more sinister version of the music that is the signature tune, used to be really very, very scary. This was Saturday tea time, half past five on a Saturday afternoon, and it would get you [hiding] behind the sofa. Wonderful stuff.

The reinvention of the show has really been an amazing thing to see. These last three Doctors have been amazing. The young kid now, Matt Smith, terrific. David Tennant was one. Chris Eccleston was excellent ... Do you know what I feel about Dr. Who's? I feel the same way as I do about the Bonds. I love them all. I love them all! I don't have favorites.

I understand that some fans would love to see Idris Elba as Dr. Who.

There's nothing Idris can't do, so who knows.