Genius, National Geographic's first TV drama, is a must-watch TV event this spring.

A big-budget dramatisation of Walter Isaacson’s acclaimed biography, Einstein: His Life and Universe, this is the real story of the scientist who became a celebrity and reveals the man behind the mind.

We caught up with the show's leading man, Oscar-winner Geoffrey Rush, to discuss the myths and magic of Einstein...

Were you any good at physics in school?

I had dreams of being an astronomer, inspired by the American space race in my childhood and teenage years, so I did maths, chemistry and physics right up until my senior year. Once we got into calculus and simple harmonic motion and equations and letters and x's and y's, I just could not respond in the way they were teaching it then. I went, 'It's just Egyptian hieroglyphics'.

Genius on National Geographic

How much did you know about Einstein before the show?

I probably had the cartoon, mythological version that most people seem to have, that he's kind of famous for his hair. It's entered the language, where people go, 'He's no Einstein'. Or Einstein can be pejorative, where school teachers go, 'Oh thank you Einstein,' if you say something smarty-pants. I had studied some physics at school, so I knew a little. But I knew nothing about what the series revealed, which is the complexity and contradictions within him, sometimes glorious, sometimes a little bit despicable, about his domestic life. It's great that long-form TV is now very popular and successful, so you get to play a character and have 10 hours with them, rather than an hour and 50 minutes in one film, which creates more biopic kind of pitfalls or cliches.

Did you know he was such a ladies man?

I didn't know about that, but I suppose if you put that equation together, he had a lot of celebrity. I think he had many young lovers because he moved around a lot. He gave up his German passport and was a bit of a gallivant. He was bright and some women find that deeply attractive. And he had humour.

Genius on National Geographic

Do you think more people might study physics after seeing how successful Einstein was with the opposite sex?

Or people might take up the violin, you don't know! It would be interesting to see if Princeton University gets more applications... One of the great revelations to me was the costume designer sending me photos and saying, 'I've got a fantastic photo of Einstein here and he's wearing the largest pink fluffy slippers,' and I went, 'Let's find a scene where that is going to be useful rather than just a trick or a joke'. And we found the right scene as he got a little bit more eccentric and a little bit more depressed and feeling as though he was yesterday's man, and he's schlepping around the house in these slippers. It was a nice touch.

Did you get to keep the slippers?

No, I should have. And the other bit that was great was a shot of him wearing slingbacks belonging to Elsa [Einstein's second wife]. They were on the beach I think, and I'm pretty certain he would have gone, 'I couldn't find my sandals this morning and I took the most practical pair of shoes nearby without any care for the fact that these are traditionally worn by women'."

Genius on National Geographic

Was the German accent tricky?

Even though Einstein didn't grow up in a faith-based, traditional orthodox Jewish family, there's still an influence of Yiddish ancestry as part of the melody of his voice. Because you're playing characters who are thinking and living in German, but it happens to be coming out in English, you're not looking at German people who have English as a second language. It's always a great conundrum for actors to go, 'How do we handle the accents without sounding like we're doing accents?' so you've just got to hopefully get the right cadence, the right melody, the right key sounds without sounding like we're in a bad old war movie or something.

Why do you think you get scripts to play geniuses?

I don't look at my CV all the time going, 'Is there a pattern?' or 'What should I do next?' But there is an accidental gravitational pull towards playing real people. I like reading biographies, memoirs, I like the way good writing in that genre can enter into the reality of that person's life and their mind. Though I'd like to think that I sometimes counterbalance it by playing a pelican [in Finding Nemo, 2003], or a pirate [in the Pirates Of The Caribbean films] or something from another planet.

Genius airs on Sunday nights on National Geographic. Catch up on episode one now on BT TV Catch-Up.

Watch National Geographic on BT TV channel 317/373 HD. 

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[Genius on National Geographic: Meet the cast and characters]

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