WHEN Wendi Peters was told that her character Cilla Battersby-Brown is suffering from osteoporosis when she returns to Coronation Street, the actress was a little sceptical.

"It sounds terrible, but the first thing I did was check that larger women can get osteoporosis, because I presumed it was frail old ladies," says the 46-year-old.

"But actually, it often happens to people who are slightly larger, because it can be down to bad diet and excessive alcohol, so everything you'd associate with Cilla."

Bold, brash and morally corrupt, the character originally appeared in the soap for four years, from 2003 to 2007, but she made a huge impact.

This is the woman, lest we forget, who put kind-hearted Rita in a prison cell for the night, after accusing her of assaulting her son Chesney (Sam Aston). "Being thrown into that storyline three months after joining, I couldn't believe it," Peters recalls.

A fan of scams, Cilla eventually found her equal in Frank Nichols, a wealthy but ruthless man she met while working in a nursing home. The pair left together for Las Vegas, but then Frank died, and using the money from a necklace he'd given her, Cilla set off to South Africa.

A DVD spin-off, Coronation Street: Out Of Africa, was filmed in 2008, in which she was reunited with Chesney and her daughter Fiz (Jennie McAlpine), but since then, very little has been known about her whereabouts.

"When she reappears, Fiz asks, 'Where've you been?', and Cilla says 'Wolverhampton'," reveals Peters, laughing. "I thought it was going to be somewhere exotic, so that made me giggle."

Chesney and Fiz, along with their respective other halves Sinead and Tyrone, and Roy, are having dinner when there's a knock at the door and Cilla makes her entrance, clutching an overnight bag and with her wrist in plaster, a result of her illness - though she doesn't divulge this.

"She's the same as ever, going, 'I'm here! Oh, you don't look very pleased to see me', as if they were going to run towards her with joy," Peters explains. "But they know exactly what she's like. They're going to think she's lying, because that's all she's done to them in the past."

When they spot that her arm's in a cast, Cilla tells them she simply banged it. It's only when Sinead sees her convulsing in pain that she's pushed towards revealing the truth.

"She knows that if she suddenly said, 'I'm not very well', they'll go, 'We don't want to know, go away'. She knows she's got to ease her way in before she admits to that."

It's not so much Fiz's reaction that gets to Cilla ("They've always had that arguing streak"), but Chesney's.

"He's the one that really knocks her for six because he's so hostile towards her, and she can't take the fact her little boy, who she was always completely in control of, has cottoned on to her."

And why wouldn't Chesney feel hostile towards his mother, the woman who left for Vegas without a backwards glance? Peters recalls watching those final scenes with her husband Kenny recently. "I wish I hadn't, I hated her," says the actress, who's decided to tone the character down a little.

"She's seven years older, nearly 50, and I just felt we needed to find a little bit more reality in her," she says - and that includes Cilla's wardrobe. "There's still a lot of gold and it's a bit too tight, but she's not as brash as she was."

It was a complete shock for Peters to hear that Corrie bosses had been in touch with her agent about bringing Cilla back.

"I'd moved on," she says. "I'm thrilled to be back, but I've been very lucky since I left."

The return stint is only six weeks long, which "fitted perfectly".

Despite having history with the show, she felt like a "little schoolgirl with first day nerves" when she arrived on set.

"It wasn't until I'd got about two or three scenes under my belt that I relaxed and thought, 'You know, this is going to be OK'."

Might Cilla make another appearance in the future?

"You can never say, 'I'm not going back', because you never know how your life is going to pan out."

l Coronation Street

Wednesday, STV, 7.30pm