Nathalie (Sally Hawkins) is an attractive and successful young woman, married to dependable GP Jeremy (Steven Mackintosh). She works as a personal shopper in a glamorous department store, where she befriends a wealthy client, Maya (Daniela Nardini).

She soon sets about trying to emulate Maya's lifestyle, and becomes seduced by the opulent city centre of Manchester, full of designer shops, bars and restaurants.

"There's almost this subliminal message that this dress or that dress will change your life and that's what it's about for Nathalie." Sally Hawkins, Actress

As her spending habits become more and more extravagent, Nathalie is forced to deal with the repercusions for both herself and her family.

"I spent a few days trailing around the shops and getting into Nathalie's head and it was kind of overwhelming," says actress Sally Hawkins.

"The colours, the music, the smells, the way they fold the clothes, the sales. You're basically buying into that world – that sparkly, shiny existence – and that escapism is exactly what it's about for Nathalie.

"There's almost this subliminal message that this dress or that dress will change your life and that's what it's about for Nathalie. I can see how easily she fell into that dark spiral – although, of course, there is no dress out there that will ever satisfy her."

"Maya has a lot of money and she enjoys spending it," reveals actress Daniela Nardini. "She thinks it's all a bit of a laugh at first and becomes a bit intoxicated by Nathalie's passion for shopping.

"Maya thinks it's all a bit of a laugh at first and becomes a bit intoxicated by Nathalie's passion for shopping." Daniela Nardini, Actress

"But after she witnesses one particularly out-of-control shopping binge, she realises that this girl is ill and that she needs help – but not from her.

"The problem is that Nathalie considers Maya one of her best friends. But Maya isn't really interested in Nathalie other than as someone who helps her buy the best. She's not what you'd call the caring type."

Producer Lisa Marie Russo explains more about the genesis for this powerful improvised film: "I am a big fan of retail therapy and have experienced the immediate gratification that comes with buying a potentially life-changing frock.

"But there can be a dark side to overindulging, and I was intrigued to learn about Madame Bovary Syndrome*, the tabloid name given to shopping addiction.

"With bankruptcy inexorably rising each year and more and more of us finding our debts debilitating I realised that looking at the human cost of spending too much was potent dramatic territory."

Next Lisa Marie spoke to her husband, the film director and writer Marc Munden (Conviction and Canterbury Tales) about developing a drama about this phenomenon.

"First-hand experience of my credit cards bills meant he immediately latched on to my suggestion," she jokes.

"I realised that looking at the human cost of spending too much was potent dramatic territory." Lisa Marie Russo, Producer

Together they approached the BBC's Ruth Caleb (Out of Control, Tomorrow La Scala!) who immediately joined forces with them.

The detailed research that followed convinced the film-makers that shopping addiction is a real addiction, a behavioural addiction that grips people and destroys lives.

Looking at the latest research from academics gave invaluable insights, as did speaking to medical practitioners treating patients with more commonly acknowledged addictive problems, such as alcoholism and compulsive eating disorders.

The groundbreaking GP Robert Lefever, founder of the Promis recovery centres, became a consultant for the drama together with one of his former patients, now a counsellor himself, Robert Batt.

Writer / Director Marc Munden spent three weeks in rehearsals with the cast, improvising on the core of a script and developing the characters.

Marc says: "Improvising is really demanding on the actors. It requires them to dig deep and it is relentless in the pursuit of the truth but it does create something that is both spontaneous and organic."

Shiny Shiny Bright New Hole In My Heart was filmed in Manchester during November 2005 and is a BBC Films production.

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