Lord Lucan mystery to be 'solved' in ITV drama starring Rory Kinnear

The mystery of what really happened to Lord Lucan will finally be “solved”, 40 years after the notorious aristocrat disappeared, in an ITV drama starring Rory Kinnear.

The peer vanished after his family's nanny, Sandra Rivett, was found dead at the home of his estranged wife in London's Belgravia in 1974.

Rivett had been bludgeoned with a lead pipe and the attacker also turned on Lady Lucan, beating her severely before she managed to escape and raise the alarm at a nearby pub.

Kinnear, currently playing Iago in the National Theatre production of Othello and soon to be seen in Channel 4 drama Southcliffe (above), will star as Lucan, who was officially declared dead by the High Court in 1999. However, reported sightings of Lucan in Australia, Ireland and South Africa have continued to fuel speculation over his fate.

The two-part ITV drama is based on John Pearson's book The Gamblers, which claims that Lucan's high-rolling gambling associates, who gathered at the Clermont Club in Mayfair, central London, and included Sir James Goldsmith and John Aspinall, spirited him out of the country after the murder.

Christopher Eccleston, the former Doctor Who actor, will play Aspinall and the cast also includes Michael Gambon.

Pearson gained unprecedented access to Lucan’s friends and acquaintances from the Clermont Club who helped him piece together the Earl’s movements on the evening of the murder.

His account places Lucan in the darkened kitchen of 46 Lower Belgrave Street with 2ft of lead piping in his hand. Rivett, lay dead before him, her skull “virtually exploded” from the force of his blows. Lady Lucan, bleeding heavily from head wounds, knelt at Lucan’s feet trying to rip off his testicles.

Lucan’s car was later found abandoned and soaked in blood in Newhaven, East Sussex, and an inquest jury declared the wealthy aristocrat the killer a year later.

Pearson’s book depicts Aspinall, Lucan and Goldsmith as a gambling set distinguished by their wealth, arrogance and misanthropy, who had no qualms over attempting to cover-up one of their number’s role in the killing of an innocent young woman.

The ITV serial, due to begin filming later this year, will be written by Jeff Pope, the man behind the channel’s Great Train Robber crime drama, Mrs Biggs.

The drama follows Lucan’s obsession with regaining custody of his children as his marriage disintegrated. Lucan is thought to have mistaken Sandra for his wife Veronica, whom he blamed for the fractures in his family life.

An ITV spokesman said: “Ultimately the drama will reveal what happened on that fateful night in November 1974.”

Francis Hopkinson, executive producer, said: “This extraordinary and tragic event has fascinated people for 40 years.

“Jeff Pope's script, based on John Pearson's book The Gamblers, brings new insight and revelations, which will surprise the audience. We are delighted that a top cast and director have come together to tell this story.”

Lucan will be directed by Adrian Shergold, who previously helmed Pierrepoint, an ITV drama portraying the life and times of Albert Pierrepoint, Britain's most prolific hangman.