What do you wake up to in the morning?

It’s quite difficult to get my mind in gear in the morning. I wake up to a small dog beside the bed, Tufty, who’s very elderly now and needs to be taken out immediately, so at least that gets me up and out. Then my husband turns on the radio and the world slowly comes into focus. 

Which TV shows make you laugh? 

The great British comedies: Dad’s Army, Porridge, Monty Python and I could watch Fawlty Towers again and again.

What makes you shout?

I’m quite good at that. I can’t bear chat shows with overbearing DJs who witter on without having any real information or listening to what their guests are saying. I’m stuck in the back of a taxi, thinking, “Please, will you just shut up!”

Who was your first crush?

Oh God, I’m embarrassed to say – Cliff Richard in Summer Holiday.

Who would you change the channel to avoid?

Our prime minister. It’s just that thing of seeing someone who doesn’t seem to belong to the world they’re talking about, who doesn’t really address the real problems. He looks so nice and so neat: I want a man with such a difficult job to look a bit more tired and rough.

Could you be tempted onto Strictly Come Dancing?

I’d definitely be intrigued because I’ve a dance background – I started ballet when I was three and went to boarding school, which was a ballet school, from the age of eight until 16. But I’ve never been asked. Instead I keep being asked to do Millionaire, Mastermind and all of those and I can’t.

Why not?

They’ll say to me, “What’s your name?” And I’ll go, “Erm, erm, erm, sorry, wait a sec…” All those schoolgirl fears I ever felt about not getting the information out in time would come  back. Ask me to do anything else – I’ll do a bungee jump – but I can’t do those shows. It’s too frightening.

Perfect night out?

I’ve always thought Mozart would be an extraordinary person to spend an evening with. His music shows such huge understanding of people and emotions and he could entertain as well – go on, give us a tune, play us a little something! Unlike Beethoven, I’m sure he wouldn’t say no.

Perfect night in?

Mike Leigh’s Life Is Sweet because it’s amusing yet kind of awful; the people are so vulnerable in it. Or the very, very funny Best in Show about American dog trainers.

You’re in forthcoming Hollywood blockbuster, The Avengers. Were you star-struck?

It made me laugh. It was so bizarre being on this big set in Santa Fe. I said as much to the director Joss Whedon and he whispered, “Shhh, I’m trying to appear cool.” Samuel L Jackson was lovely, so professional. Scarlett Johansson looked sad, so lonely, sitting on the steps of her Winnebago. One wanted to go and give her a hug and I thought, “You can’t because you just don’t know her.”

This is an edited version of an article from the issue of Radio Times magazine that went on sale 31 January 2012.

You can see Jenny in Call the Midwife, tonight on BBC1 at 8pm