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He's often said that if he'd grown up in a slightly different place, slightly different circumstances and slightly different time, it's something he might have seen himself doing." His father appeared in a non-speaking role as a footman in Doctor Who.
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I think he had a bit of a notion for it himself. "Being a minister is sort of like acting and my dad has always been very supportive. Would Sandy have liked his son to follow him into the church? "No, no, we all went different ways and that's absolutely as our parents would have had it." If anything, he says, his dad would have fancied a go at Tennant's job. His father Sandy was the local Church of Scotland minister. Tennant was born David John McDonald and grew up with his brother and sister in a manse in Paisley, Scotland. And I remember understanding very clearly the difference between the fantasy and reality of that, and that making it even more exciting." "I remember a conversation with my parents about who the people on the TV were, and learning they were actors and they acted out this story and just thinking that was the most fantastic notion, and that's what I want to do. So I was just very fortunate that as I grew up and began to understand what that actually was, the idea developed consistently." He stops, and says actually that's not right – he did have a sense of what acting was back then. "I know it's absurd and precocious and, of course, at three, you don't really know what that means. Is it true he knew he wanted to be an actor when he was three years old? He laughs, embarrassed. Well, what could be better, he says – acting in a great play to a sold-out audience with one of your best mates? (Tate also starred with him in Doctor Who.) This is what makes him so likable – you don't feel there is a hidden beef, an itch of resentment that he isn't a global superstar. I tell him I loved the fact he looked so chuffed at the end. Tennant has a wonderful way of demystifying Shakespearean verse without patronising it, mining every word for maximum humour or pathos. In Much Ado, he is a brilliant Benedick – shallow, laddish and witty, he gradually learns how to show his love. Sure, he's funny, but it's not the most challenging of roles. In Fright Night, a remake of the 1985 original, he plays veteran vampire hunter Peter Vincent like Russell Brand on speed. Maybe this will change with his first Hollywood movie. Perhaps that's the biggest surprise – that for all his popularity and talent, he isn't a huge film star. He has also romped as Casanova, probed as DI Carlisle in the TV musical-drama Blackpool, theorised as cerebral scientist Arthur Eddington in Einstein And Eddington (stick a pair of specs on him and he's as dull as the next man), played Hamlet quite beautifully (awkward and paranoid, yet graceful) and appeared in a number of none-too-impressive movies. For many he is the Doctor – geeky, manic and a little bit gorgeous. Tennant is still best known as the Doctor. "There's something Greek about it, isn't there?" Apparently he said it like a dead fish." Has he been hacked? Well, he has his suspicions, but the stories that surprised him weren't in News International tabloids, and he's more interested in the meta-drama than any tiny role he might have played. "Rupert's just said it's the most humbling day of his life. The police, the press, the politicians all in it together – perfect conspiracy. He's obsessed with hacking, can't stop reading about it. Here he is in his skinny jeans and Beatles T-shirt, bubbling with enthusiasm, and absurdly boyish. Today, Tennant, 40, looks like a teenager posing as an adult. I've never seen an actor so happy in his job. It's the encore when Tennant skips across the stage, grinning from ear to ear, and you just know there's nothing on earth he'd rather be doing. It's not when David Tennant's Benedick makes his entrance as a sun-bronzed prat in a golf buggy, nor his Cary Grant-style rat-a-tat-tat delivery of lines such as, "I would my horse had the speed of your tongue", not even when he finally gets to kiss Catherine Tate's Beatrice.
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T here's a moment in the current production of Much Ado About Nothing that I particularly love.
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