Early in 1995, the glamorous former wife of fashion magnate Maurizio Gucci went shopping in Milan for a special outfit.
This in itself was not unusual since in those days Patrizia Reggiani was something of a designer clothes horse, fond of colourful frocks and film star dark glasses.
Except on this occasion she bought an elegant black suit and veil to wear to 46-year-old Maurizio's funeral – even though he was very much alive and, by all accounts, in rude health. Patrizia knew, however, what was coming next.
Springing up the steps of his offices on Milan's elegant Via Palestro one morning three months later, Maurizio was approached from behind by a dark-haired man who pulled out a gun and put three bullets in his back and a fourth in his head.
The murder transfixed Italy. Before their acrimonious split, Maurizio, the last of the Gucci family dynasty to run the luxury brand, and Patrizia, his flamboyant, strong-willed wife, had been a celebrity power couple.
A tip-off led to Patrizia's arrest in 1997. A search of her Cartier diary revealed she had marked the date of Maurizio's murder with the word 'Paradise' and after a sensational trial, she was convicted of hiring a hitman to kill him, earning herself the sobriquet Black Widow.
Patrizia Reggiani's ex-best friend Giuseppina 'Pina' Auriemma (left) was convicted of acting as the 'middle woman' in the hit of Maurizio Gucci, liaising with the organiser of the murder
Few in this high-living couple's gilded world were better placed than Patrizia's former best friend Giuseppina 'Pina' Auriemma to observe her downfall – a story of love, betrayal, sexual jealousy and bloody revenge set against a high-fashion backdrop that is now being retold in Ridley Scott's film House Of Gucci.
Speaking to The Mail on Sunday in her first interview, Pina recalls Patrizia's ruthlessness, typified, she says, by the prematurely purchased funeral outfit on a shopping trip that has remained secret until now.
And Pina reveals her lifelong bitterness at being drawn into the Black Widow's web and being ostracised from her family. For Pina was convicted of acting as the 'middle woman' in the hit, liaising with the organiser of the murder.
After her arrest, Pina was described in the Italian media as a maga – sorcerer or fortune-teller – and dubbed the Black Witch.
Hitting back at her old friend, who is played by Lady Gaga in the film, Pina, 75, says: 'She is evil. My life has been completely ruined by that woman.
'I thought Patrizia was a fun and exciting person when we first met, but now I see that she is a shallow narcissist who only cares about money and will step on anyone to get what she wants.'
Her bitterness stems in no small part from Patrizia's insistence that Pina was to blame for the murder, which she vehemently denies. Both women served their time in San Vittore prison in Milan, where for years they determinedly avoided one another.
At Patrizia's trial, it was claimed she ordered her ex-husband's murder because of her 'insatiable hatred' of his new life with another woman.
There were other factors too. Maurizio had been forced to sell his stake in Gucci 18 months before he died, a decision Patrizia never forgave, since everything 'she was stemmed from being a Gucci', says a Milanese fashion writer.
'It was her whole identity, even as an ex-wife. She was furious with Maurizio for selling out.'
Pina says that in the aftermath of the break-up, Patrizia threatened to throw herself off the balcony of her luxury apartment, became hooked on anti-anxiety drugs and, in rage, once tore apart the leather walls of an elevator with her nails.
In the film, Pina, played by Salma Hayek, is depicted as an eccentric, dowdy mystic whom Patrizia contacts after watching her on a clairvoyant TV show.
It was claimed Patrizia ordered her ex-husband's murder due to her 'hatred' of his new life with another woman. Pictured: Lady Gaga as Patrizia and Adam Driver as Maurizio
The reality, Pina says, is very different. 'I have never practised magic or fortune telling – I have no interest in it – and it is defamatory to say I do.
'It was Patrizia and Maurizio that were obsessed with tarot cards and mediums. Whenever they arrived in a new place, the first thing they would do was find the local psychic.'
The two women met by chance in the late 1970s at the Excelsior spa hotel on the volcanic Italian island of Ischia.
'I liked Patrizia immediately,' Pina says. 'We were both young and fun, in our 30s. I had no idea who she was as she wasn't famous back then, but I remember she was wearing a pearl bathing suit and she was dripping in jewellery.
'She refused to eat, as was the custom of high society women back then, so we spent most of our time gossiping in the spa. At the end of the week, her husband joined us, which made it more fun as he liked to eat well and drink champagne.'
Pina's impression of Maurizio was that he 'seemed like a nice person, if a bit gullible and naïve, and we got on well'.
'You could tell Patrizia wore the trousers in the relationship and he seemed completely besotted with her. Whenever she crossed a room, he could not take his eyes off her.'
Following the death of his father in 1983, Maurizio inherited 50 per cent of the company but the Gucci brand had lost its lustre, thanks to its famous name being over-licensed.
According to Pina, her socialite friend believed she was stronger, and therefore more 'Gucci', than anyone else in the family. She pushed Maurizio into a power struggle with his uncle Aldo, played by Al Pacino in the film.
Her ambitions to be the First Lady of Gucci hit the buffers, however, when she was out-manoeuvred by the firm's executives.
She was forced into life as a bored housewife, albeit one with a 200ft yacht, a ski chalet in St Moritz, a holiday home in Acapulco and a farm in Connecticut. At one point, she was said to be spending £9,000 a month on orchids.
What she really wanted, though, was respect, which proved impossible to buy.
Pina says: 'Patrizia would call me at all times of day and night
