Every Christmas Eve, Eddie Redmayne cooks a ham. He tends to this ham with the utmost care and devotion, adding a little brown sugar here; a few more cloves there. It takes him hours, if not a whole day. For those of us who partake regularly of the Redmayne ham – he and I go back a long way – it seems to get better every Christmas, as if he's been quietly, stealthily striving to improve the recipe all year round. Yet no matter how magnificent it tastes, how tenderly it melts in the mouth, the actor will brook no compliments of the ham. Invariably, he will instead point out what he could, should have done better.
I am struck by the ham analogy during a recent interview with Redmayne. Exactly 10 years since he was plucked from Cambridge University to play Viola opposite Mark Rylance's Olivia in a 400th-anniversary production of Twelfth Night, he has just learned that his current role as Richard II at the Donmar Warehouse has been crowned Best Shakespearean Performance at the Critics' Circle Awards – no mean feat, given the season has also seen heavyweight Shakespeare contributions from the likes of Spacey, Tennant, Sheen and Fiennes.
In the decade between Viola and Richard, Redmayne has worked fastidiously and uncompromisingly. Allergic to anything resembling complacency, he rarely takes a day off. Now he is talking to me over a cup of tea before heading back to the theatre for that night's performance, and he is radiant with excitement at the Critics' Circle news. "It's just the loveliest, loveliest thing that could have happened," he admits. But where most actors would take such a prize as cue to relax and enjoy the last weeks of the run, Redmayne shakes his head. He's going back to work.
"Because you never get it right," he insists. "You never get it close to getting it right, you never get one line exactly how your notion of it should be. That's what's so exciting about theatre. Most actors hate watching their own films because all you can see is the glaring mistakes, your own tricks and ticks. But people often ask, how can you do the same play night after night for months on end and not get bored? And that's the reason. In theatre you always have the chance to try and fix what you did the night before."
It seems remarkable that London-born Redmayne, who has just turned 30 and is having, by any definition, a golden moment, should remain so self-critical. As well as giving his Richard every night, making lines like "I live by bread like you, feel want/ Taste grief, need friends" seem revelatory, he is also gracing Sunday night TV screens as Stephen Wraysford in a landmark BBC1 adaptation of Sebastian Faulks's Birdsong, and charming cinema audiences in My Week With Marilyn. As soon as Richard II closes, the former Eton and Cambridge choral scholar is off to play (and sing) Marius in Tom Hooper's big-screen musical adaptation of Les Misérables, with Russell Crowe, Hugh Jackman, Helena Bonham Carter and Anne Hathaway. And with major theatre awards from the Olivier to the Tony already to his name, he is now up for a Bafta – this year's Rising Star Award, which is voted for by the public – and looking, increasingly, like the one to beat.
But this is also the young man who was so unconvinced he would make it as an actor that he seriously considered other career options after graduating, including art history and banking (his father and one of his three brothers are in finance; nobody else in his family is in the arts). "I didn't go to drama school, so there was no official transformation stage, no moment where I got a certificate, even a bit of paper, saying 'right, you're allowed to do this now.'".
"After university, I gave myself a year. I was working in a pub and doing excruciating auditions and wondering if my new agent who'd taken this huge punt on me would sack me, and I remember getting a part in an episode of Doctors and it was probably the most exciting thing that had ever happened in my life. Then I went to Liverpool to do a play called Master Harold... and the Boys and I was living in a hostel on my own for three months and it was the most wonderful experience. I started to think, secretly, 'Well, maybe I can do this.' But I came back to London and nobody took any notice and I went back to work at the pub. I always felt a bit fraudulent, like I was waiting to be exposed."
Munching a biscuit, he contemplates this. "In a way, I still do. I still feel this incredible sense of gratitude that anybody actually lets me do this professionally."
In any other actor, this might come across as galling false modesty. Given his current ubiquity it's easy to imagine Redmayne's success has arrived largely overnight; but that "star" to which the Bafta nomination alludes has been gradually rising for 10 years. It may also be tempting, considering the green eyes, 6ft 1in frame, and ridiculous cheekbones that have won him Burberry modelling contracts, to assume that this is just another talented pretty boy who happened to get lucky. But ever since Rylance gave him that first big break, Redmayne has personified the old adage that luck is merely what happens when hard work meets opportunity. As his CV has swelled, so too has his dedication; the more professional triumphs that have come his way, the more he has put his head down and worked harder.
"Listen, acting is not surgery," he remarks. "It's entertainment. You're doing something to hopefully move people, to make them laugh, to transport them. But actors are vulnerable, and the reason we're vulnerable is that we're always trying to recreate human behaviour. And any human being has the right to look at that behaviour and decide if it looks real to them or not.
"Everyone has that capacity for judgment, everyone can turn around and say, 'Sorry, but I just don't believe that.' So if you have thin skin – and I don't have particularly thick skin – then your need to constantly please people, well... it's completely impossible. That's why I still feel I've got so much work to do, to really try and nail this thing."
Birdsong ends Sunday, 9pm on BBC1. Richard II is at the Donmar Warehouse, London (www.donmarwarehouse.com) until 4 February. My Week with Marilyn is in cinemas now