Young nurse Janet Dawkins lives a normal life in Northolt, north-west London. But everything then changes when she slips and falls into the Grand Canyon while on holiday in America. She’s rescued by Thermoman, the world’s best known and favorite superhero. From that moment on her life is never quite the same again. Thermoman, who by day is Irish health food shop owner George, is smitten by her.

Actress Emily Joyce who plays Janet, says of her: "She’s fairly sassy, knows her own mind and is very much into her career. Her whole world is turned upside down by the appearance of George. He falls in love with her and follows her back to Northolt, and tries to woo her as George because he doesn’t want her just to fall in love with Thermoman. Janet does indeed fall in love with George, who is slightly bumbling but rather charming. At first she thinks he’s very funny. Then it turns out that he actually means everything that he is saying.

"She thinks he says all these odd things and is being really literal and it turns out that he actually means everything he says. Eventually he tells her that he is actually Thermoman – and he proves it. Then she soon discovers that going out with a superhero has certain benefits – like he’s rather good in bed and she’ll never have to worry about opening jars of marmite again.

“There are disadvantages too, though, like having to keep it a secret all the time – and his constantly wanting to come to her rescue even when she just has the slightest problem. But she puts up with that because she loves him.

"Her parents think he’s very odd and her mother particularly would like Janet to go out with her boss, Piers. Janet thinks Piers is a prat really, as do most people except for her mother and Piers himself, who obviously thinks he’s absolutely fantastic."

As a youngster Emily was no great fan of superheroes. "I was never into Batman or anything like that," she says. "I never wanted to be rescued but instead I wanted to be one of Charlie’s Angels."

Emily’s last sitcom role was the Channel 4 series In Exile in 1998. "When I saw the script for My Hero for the first time I just thought it was very funny," she says. "I’m really pleased to be doing it."

Emily is the youngest of three girls. Their father is an architect and their mother a college inspector, but all three girls are in the entertainment business.

Rachel, the eldest of the three, is an actress and is currently with the Royal Shakespeare Company, and Amy produces Channel 4’s The Real Holiday Show.

"Mum always loved the theatre and took us to see plays when we were youngsters," says Emily. "I was terribly shy as a kid and Rachel encouraged me to audition with the National Youth Theatre when I was 15. I got in, and I found I could actually communicate with these people and have a laugh – and actually open my mouth! I was only there for two weeks but from then on I got the acting bug and the shyness and lack of confidence began to go."

Before going to drama school, Emily worked for a year for Vogue magazine. "I was the assistant merchandise editor," she says. "When you see on fashion pages a list of everything the model is wearing and where it is from… well, my job was to phone up and find out."

At the age of 17, Emily was lead singer of a rock band called In Spite of All That. "We wrote our own stuff and did gigs all over the place and we actually recorded an album which I’ve never heard," she says.

"I was in the band for three years including the time I went to drama school. I had to make a decision between acting and singing because the music was getting more serious.

"I chose acting because you can still get parts in EastEnders when you are 90 but you can’t really be in the pop charts!"

Emily’s contemporaries at drama school included Minnie Driver, who has gone on to great success in Hollywood. "She was in the term above me and she used to play my mother," laughs Emily. "She was really nice and very talented."

Her first break came with a season with the Royal Shakespeare Company and her first television role was in the ITV drama Cracker. "I played the murderess in the final episode of the series," she says.

"My character had to sleep with and then electrocute lots of young men and she became obsessed with Fitz. It was a fantastic first role to get and after that I got a spate of roles playing mad people in shows like Wycliffe and Casualty."

In 1999, she starred alongside Stephen Tompkinson and Robson Green in the first series of the ITV drama Grafters – although in that she had a blonde bob hair style compared to short and dark as it is now.