5 minutes with: Rudi Dharmalingam – 'We are rehearsing two versions of Mary Stuart'

I was never part of a youth theatre growing up, I didn’t even perform in the school plays. My passion when I was a kid was table tennis. I wasn't hugely academic at school and drama was the one subject I seemed to do quite well in. By the time I did my theatre studies A-Level I decided I wanted to go further with it, but realised I had nothing on my CV to show I was serious about it. So I applied to the National Youth Theatre and got in and it went from there.

The History Boys was my first proper job. I was covering for Dominic Cooper. We did a world tour and went to Broadway and I got to go on for three weeks which was wonderful. Most of us were in our mid-twenties and I remember Alan Bennett saying in the rehearsal room that in many years, people will look back on this production and remember where we all started. It was a very special show and it was a crazy time.

I learnt so much from watching people like the late Richard Griffiths, Frances de la Tour and Clive Merrison. I see that whole year and a half as an apprenticeship, because I soaked up everything I could. I still believe that on the job training is the best training you can have as an actor.

We are essentially working on two versions of every scene of Mary Stuart. There’s a coin toss [at the beginning] which will decide which role Lia Williams and Juliet Stevenson take on that night – either Mary Stuart or Elizabeth I. I’ve never worked like this before, but it is very thrilling because it keeps us all on our toes.

The play is based on what happened to Mary Queen of Scots, but the character I play is fictional. Mary Queen of Scots spent 20 years in prison and the play is about her last few days there before she gets executed. Schiller wrote in my my character Mortimer, who has fallen in love with Mary, without actually having met or seen her. He has made it his mission to free Mary from prison and maybe kill Elizabeth while he’s at it.

Robert Icke might give off a slightly intense aura, but he’s actually a really regular guy. I love his process because it’s always organic. He doesn’t have a structured staging plan prior to rehearsals so basically us actors discover it ourselves. The design lends itself to that as well: it enables actors to explore things very spontaneously.

X at the Royal Court was a show that will stay with me forever. Obviously you are proud of every show you do but sometimes you have one or two shows that leave an imprint on you. I don’t think anyone of us wanted X to end, it felt like it deserved another life. Textually it was very, very ,very complicated and I remember losing sleep over it. The second half of the play had very little logic to it. I went to some dark places – character-wise – during that show.

I am drawn to anything that isn’t easy. Any form of challenge. Over the last five years or so I’ve been very lucky in that I’ve been able to play a really diverse range of characters, in diverse situations and I am eternally grateful to the people who have given me those opportunities.

Mary Stuart is in previews at the Almeida Theatre, opening on 15 December and running until 21 January.