The Madonna of the Yarnwinder by Leonardo da Vinci was the most valuable painting ever stolen in Britain. Twenty years on Olivia Graham tells the inside story of how her dad’s role in getting the painting back led to him standing trial for extortion.

I was 18 when my dad took me to one side in the Liverpool pub he owned.

He told me something amazing was going to happen – something unbelievable – that one day I could tell the grandkids about.

At the time I was too stunned to ask him anything about it.

But now I have made a podcast for BBC Sounds, where I ask plenty of questions about what really happened when my dad rescued a stolen 16th Century masterpiece.

The story begins on the morning of 27 August 2003, when an old VW Golf GTI drove through the Dumfriesshire countryside and pulled up outside Drumlanrig Castle, the home of the Duke of Buccleuch – one of the richest men in the country.

Two men got out of their car and made their way into the castle where they took tour guide Alison Russell by surprise.

One of them put his hand over her mouth and told her to “get down on the floor”. Then they prised the Leonardo masterpiece off the wall with an axe and ran to their getaway car.

The whole operation took just a few minutes.

The day after the heist a press conference was held. The Madonna of the Yarnwinder was a 500-year-old painting by one of the most famous artists in the world and was thought to be worth £40m. It was big news around the world.

Mark Dalrymple, the fine art loss adjuster representing the painting’s insurers, announced a “substantial” reward for information leading to its return.

An extensive police operation kicked into gear but the criminals slipped the net.

Four years later, the painting had fallen off the radar.

By this time it was in the possession of a group in Liverpool who had acquired it as collateral in a failed property deal. They wanted to recoup the money they had lost – £700,000. But how?

That’s where my dad comes in.

Robbie Graham was a man of many parts.

He wasn’t college or university educated and I don’t think he left school with any qualifications but this didn’t stop him from thriving in many different lines of work.

He saw everything as an opportunity, the next big break.

Some of his business ideas were dead in the water but others opened up exciting opportunities, such as his private investigations agency and his website reuniting stolen items with their owners.

It was a small-scale operation called Stolen Stuff Reunited but it attracted the attention of some surprising clients.

So it was that in June 2007 two men, known as J and Frank, came to Robbie and his business partner Jackie Doyle with a proposal.

Could they return The Madonna of the Yarnwinder to its owner and claim the reward?

Robbie and Jackie were interested, but only if they could do it lawfully – so they got in touch with a lawyer, Marshall Ronald.

He contacted David Boyce, a solicitor at respected Scottish firm HBJ Gateley Wareing.

David, and his HBJ partner Callum Jones, advised Marshall to establish contact with the loss adjuster, Mark Dalrymple. So Marshall sent him an email.

“I immediately thought Mr Ronald was deceptive,” Mark told me.

This instant reaction shaped everything that followed, although that wouldn’t become apparent until later.

Marshall didn’t deal with Mark Dalrymple directly. Instead he was passed on to a third party who was described to him as a representative of the Duke of Buccleuch.

A reward of £2m was settled upon quickly.

It would be paid into an escrow account – held by a third party – in advance of the painting being returned.

Marshall would not be able access the cash until the painting was back, but he would be able to see the money sitting in the account waiting for him.

The group holding the Madonna agreed to hand over the painting in exchange for a £700,000 cut of the reward money.

A plan was formed. Robbie would collect the artwork, take it to the offices of HBJ Gately Wareing in Glasgow for repatriation and claim the reward.

But then the Duke changed his mind.

Apparently no money was to leave his account until after the Madonna had been returned.

The people holding the painting weren’t happy with this development. It shook their confidence. They demanded payment upfront.

Where were Robbie and Marshall going to get their hands on £700,000 in cash?

“It was the most stressful week of my life,” remembers Marshall.

Negotiations led to the group agreeing to a reduced payment of £350,000 in cash, plus a banker’s draft for £150,000. Marshall was just about able to lay his hands on that amount of money.

So the handover was on.

Hale Village lies a few miles southeast of Liverpool city centre. It was here on Wednesday 3 October 2007 that Robbie pulled in to the car park of the Childe of Hale pub with the cash and banker’s draft.

It was J who turned up to take the money, but he disappeared without handing over the painting.

By the time he came back – four hours later – my dad had been joined by Jackie. J came up to the car carrying something covered in a white blanket.

I can only imagine what went through Robbie and Jackie’s minds as they took hold of the package. I do know that they unwrapped one corner and had a peek. Then Robbie called Marshall.

“The lady is on her way home,” he said.

At 11:05am the following day, Robbie, Jackie and Marshall met outside the offices of HBJ Gateley Wareing – ready for a heroes’ welcome.

But that’s not what happened.

Mark Dalrymple tells me: “I knew that Glasgow and Dumfries police were there and had surrounded the offices.”

This had been the plan all along. Get the painting back and then swoop in and make arrests.

The reward hadn’t been real, just a part of a police operation.

I remember how I found everything out. My sister picked me up from the train station at Ormskirk and it came out all in one go.

She said: “Dad has been arrested, our house has been raided and we are on the front page of the local paper.”

Two-and-a-half years later, Marshall, Robbie, Jackie, Callum Jones and David Boyce stood trial.

The charge was conspiracy to extort.

The defence relied upon proving the group had been led by the nose by officials. It wasn’t a straightforward case.

On 20 April 2010, Callum and David were found not guilty.

The charge against Robbie, Jackie, and Marshall was found not proven.

My dad phoned me not long after the verdict. I don’t remember exactly what he said. It was something like: “We did it and I’ll be home in a few days. I love you”.

The Duke of Buccleuch never got to see his painting returned. He died on 4 September 2007 – one month before The Madonna of the Yarnwinder was delivered to the solicitors’ offices.

No-one has been arrested for the theft of the painting and no reward paid out for its return. The Madonna of the Yarnwinder currently hangs in the Scottish National Gallery in Edinburgh.

My dad tried to move on after the trial.

He threw himself into his family and his next big plan – with him there was always something new.

But he also developed a new appreciation for art and I remember him dragging us round galleries on family holidays.

He died on 19 December 2013, aged just 61.

My dad’s funeral, like his life, was one big party filled with wonderful people, lots of stories, love and laughter.

He was a man for whom the possibilities of any given day seemed endless.

I miss him all the time. I didn’t think I could love and appreciate him any more.

In accordance with his wishes, my dad’s coffin featured a photo of him – one he really loved.

His arm is proudly wrapped around a painting – Leonardo da Vinci’s The Madonna of the Yarnwinder.

The Missing Madonna podcast is available on BBC Sounds.