The mistress of a murdered aristocrat has spoken of her love for him in a new television documentary charting his tragic downfall.

Former nightclub hostess Nadia Orche was having an affair with the 10th Earl of Shaftesbury, Anthony Ashley Cooper, when his estranged wife Jamila M'Barek and her brother Mohammed plotted to kill him at the marital home on the French Riviera and dumped his body on a remote mountainside in 2004.

Miss Orche, 36, from Hove, told Channel 4's Cutting Edge of her blissful months with the Earl before his death and how his wife manipulated him for money before committing murder when she realised she would lose a share of his inheritance.

But Jamila's sister Naima M'Barek hit out at Miss Orche, launching an angry tirade at her for destroying her sibling's marriage.

And Miss Orche revealed the Earl, who abandoned his aristocratic lifestyle in England, where he had a home in Hove, to indulge in women, drink and drugs as an international playboy in France in his 60s, wrote her a series of lurid love letters just after he married her sister.

Miss Orche said the Earl, who had drink problems, persuaded her to quit her job as a hostess girl and move in with him at a hideaway love-nest in the south of France.

She said: "I found him different to most men. He was very kind and respectful, he spoke calmly and he knew how to treat a lady.

"He started to tell me about his situation, that he was married to a Tunisian woman. He kept on telling me that it was the biggest mistake of his life.

"Her only goal was to take and take and take from him. She studied his personality and used his weaknesses to get what she wanted.

"During the time I spent with him, I made him very happy. We spent some very simple days together, simple outings, a simple life.

"He drank less when he was with me. He was a normal man with normal needs. He was affectionate and soft. He had no strange habits, at least not with me."

She added: "I did not steal her (Jamila's) husband. I met him and he did not want to see her anymore.

"She did not love him anymore. She did not want him. She just wanted his money."

But Naima, facing the TV camera to speak directly to Miss Orche, said: You will never have any luck in your life because you separated two people who loved each other.

"Anthony is not here anymore, his bank account is closed.

"My sister came to me in such a state (after finding out the Earl was having an affair with Miss Orche) that I thought she had Parkinson's disease. You messed her up."

Naima also claimed he was making advances on her behind Jamila's back.

She said: "I was always getting messages from him. He kept calling me from the (honeymoon) suite, I love you, Naima, you're so beautiful, you are my dream'."

She showed the filmmakers a pile of love letters the Earl, whose ancestral estate was in Dorset, sent her just after marrying her sister.

The Earl and Jamila, who was also a former bar hostess, moved from Paris to Cannes but within months he was looking for new women and cruising the hostess bars, where he met Miss Orche.

Mohammed had a history of psychiatric illness and was paid by Jamila £105,000 to murder him.

The 66-year-old Earl was lured to his luxury marital apartment by Jamila where Mohammed strangled him to death before dumping his body in a remote ravine in the Alps. It was found five months later, half-eaten by wild animals.

In May 2007, Jamila, 45, and Mohammed, 43, were convicted by a French jury of murder and were sentenced to 25 years in jail.

The documentary traces the Earl's tragic downfall from an English aristocrat to his later life of glamour and vice in France.

He had two failed marriages in England and had been unfaithful in both.

During the course of 1999, his mother died, he was going through his second divorce, he gave up the family's ancestral mansion to avoid monumental death duties, and he lost his role in society when Tony Blair abolished the right of hereditary peers to sit in the House of Lords.

As a result, he moved to France where he squandered his fortune in hostess bars and developed a scandalous love life.

"Cutting Edge: Who Killed the Playboy Earl?" is on Channel 4 at 9pm on Thursday.