When the curtain rises on the opening night of the Alhambra pantomime tonight, Wicked Queen Sian Reeves will enjoy a moment of personal triumph.

Not long ago she was bed-ridden and in constant pain, fearing she may never work again.

Three years ago Sian suffered terrible injuries in a backstage accident while rehearsing for a play at a London theatre. She fell through a trapdoor and was impaled on a ladder, ending up with a punctured lung and crushed ribcage. She was barely able to move for almost a year.

“I’d done 25 years in the business and was thinking that was my lot, and that I’d have to re-train as a teacher,” says Sian, 45.

Thankfully, largely due to “sheer grit and determination”, she returned to acting, and this year won praise from viewers and critics for her chilling performance as twisted vicar’s stalker Sally Spode in Emmerdale. Keen to return to theatre, Sian starred in three-hander Misconception at this year’s Edinburgh Festival. “Theatre was what I started doing – I was in the original cast of Les Miserables,” she says. “Doing Edinburgh eased me in, and now this is my big return to theatre. Initially panto felt like a baptism of fire, but rehearsals have gone so well. After four solid days it felt like we’d been together for weeks. It’s very physical, but I look after myself. I’ve done a 15-month stretch in theatre, so I can cope.”

Taking a break from rehearsals at the Alhambra, Sian is relaxed, chatty and prone to fits of laughter. She even throws in an impressive Rick Astley impression. Playing the Wicked Queen enables her to showcase the impressive singing voice that earned her the winner’s crown on Just The Two Of Us, the BBC1 show partnering celebrities with professional singers, in 2006.

“I started with Rick Astley as my partner then he suddenly walked out – ‘Shaaarn luv, I just can’t do it,’ he said – so they put me with Russell Watson,” says Sian. “I’m not sure he liked me at first, but it worked out well. I used to get so nervous I’d faint before our live performances. People used to find me in the back under my coat.”

There’ll be no fainting backstage at the Alhambra though. “I can’t wait to get out there!” says Sian. “It’s going to be a fantastic show. I have two big scenes with the 3D magic mirror, which children are going to love. Panto is a real responsibility because it can be a child’s first experience of live theatre – they believe in everything that’s going on. My daughter is 15 now, so she’s a non-believer – it’s a little sad when that happens. From the ages of nought to 11, children are marvellous.”

Sian is playing the Wicked Queen as a spoiled princess. “She stamps her feet a lot then becomes increasingly vile,” she grins. “I’ve never been a baddie on stage and I’m not sure how I’ll feel if I get booed at the end – but I suppose that means you’ve done a good job. I’m hoping to scare some of my Emmerdale friends who are coming along!”

She’s been enjoying getting to know her co-star, Bradford’s favourite funnyman Billy Pearce. “As soon as I met him, I knew he was a diamond,” she says. “The Alhambra is fabulous. I was last here in 1993, in Babes In The Wood with Russ Abbot.”

Fans of the Yorkshire soap will know Sian as psychotic stalker Sally, whose obsession with mild-mannered vicar Ashley Thomas led to her reign of terror; from setting the church on fire, with vicar’s wife Laurel inside, to drugging Ashley before seducing him. She was last seen earlier this year being bundled into a police car.

“I’d like to see her return – with Ashley’s triplets,” smiles Sian. “She was a joy to play. She started out as Ashley’s nice old flame and ended up a mad woman tearing his family apart.”

West Bromwich-born Sian shot to fame as feisty Sydney Henshall in TV drama Cutting It. She was also in sitcoms Lunch Monkeys and City Lights, and played domestic violence victim Hannah Temple in Hope Springs, about four ex-cons in hiding following a multi-million pound heist.

“I loved doing that. It had a bit of everything and people seemed to enjoy it, it’s a real shame there wasn’t a second series,” says Sian.

Next year Sian will be reunited with Angela Griffin, her Cutting It co-star, on new Sky TV comedy drama Mount Pleasant, starring Sally Lindsay and Bobby Ball.

“Having been in so much pain, thinking I may never work again, to be doing a bit of everything from what I did years ago – singing, theatre, comedy – is wonderful,” smiles Sian.

Snow White And The Seven Dwarfs runs at the Alhambra from tonight until February 6. For tickets, ring (01274) 432000.