Judi Dench plays the real-life KGB mole OAP who stole nuke secrets in Red Joan

FOR decades the secret services were left chasing shadows in the hunt for agent Hola – Russia’s most effective spy in Britain.

This traitor in our midst had handed over nuclear bomb-related documents so highly classified that most of the Cabinet did not know they existed.

The information helped the communist state catch up with Britain in the race to build the deadliest weapons ever seen.

So who was Hola? And how had the mole managed to infiltrate our system?

When the spy was eventually unmasked half a century later in 1999, the identity came as a huge shock.

The KGB’s “man on the inside” was in fact Melita Norwood, a grey-haired, tea-drinking woman in her eighties who enjoyed tending the roses at her semi-detached home in suburban South East London.

Described as “the most important female agent ever recruited by the USSR”, she was considered more valuable than infamous British Reds Kim Philby or Guy Burgess. She had evaded detection by playing the dutiful housewife and mother.

Now her double life has inspired the film Red Joan, with Dame Judi Dench co-starring in the title role.

Her name has been changed and the story sexed up, but there is no doubt it is based on unlikely operative Norwood.

Despite having put millions of lives at risk, Norwood, who died in 2005 aged 93, was never prosecuted for her treachery — and she never expressed regret for her actions.

This week her daughter defended her mum’s decision to spy for the Soviets from 1934 to 1972.

Anita Ferguson, 75, who lives in a small house in the West Midlands, told The Sun: “She did it to help the Russian people.

“Sir Winston Churchill’s wife started sending packages to support the Russians. We sent soldiers there to die against Hitler. All she was doing was trying to help people — it wasn’t selfish.”

Norwood’s excuse for helping dictator Joseph Stalin in his pursuit of the atomic bomb at the end of World War Two was that she feared the US, which already had nukes, would end Russia’s socialist dream.

How she came to be in a position to do that is a source of great embarrassment to MI5.

Despite being investigated by them TEN times, and not hiding her socialist sympathies, Norwood secured a job that gave her access to Britain’s nuclear secrets.

She was born in Bournemouth to Alexander Sirnis, a Latvian immigrant with strong Communist ties. Following in her father’s footsteps, Norwood joined the Communist Party.

She was recruited as a Russian agent by journalist Andrew Rothstein in 1934, at the age of just 22.

Having dropped out of the University of Southampton after just one year, Norwood joined a spy ring trying to steal details of a naval gun from Woolwich in 1937.

While three of the gang were uncovered, she escaped discovery and took up a job as a secretary at the British Non-Ferrous Metals Research Association in the same year.

This was to be her big chance, as the association played a key part in our nuclear project, codenamed Tube Alloys when it began four years later.

Her ability to understand technical material meant she was promoted to secretary to the director.

Paperwork about how to safely enrich uranium, which would be used in bombs, passed across his desk and was put in his safe.

Norwood would make copies then deliver them to her KGB handlers. Daughter Anita tried to downplay the damage Norwood had done, saying: “There are questions about whether it was really useful at all to the Russians. She did say she spied, but what? She was only a secretary.”

But Cambridge University’s Dr David Burke, who interviewed Norwood for a book about her life, The Spy Who Came In From The Co-Op, insisted last night: “She was a crucial spy.

“It was incredibly valuable. The Russians knew how to build a bomb, but they didn’t know how to build a nuclear reactor to extract the uranium.

“It was only when Melita Norwood gave them British Non-Ferrous Metals’ solution that they could test a bomb in 1949, when British Intelligence had been saying they would not get there before the mid-Fifties.”

Norwood never revealed to anyone what she was up to, not even to her Left-leaning husband Hilary, a maths teacher.

He suspected she had been meeting KGB agents when she arrived back late from work, but did not know the extent of her crimes.

Her handlers were top Soviet spies Ursula Kuczynski, aka Red Sonja, and playboy Gordon Lonsdale, who was jailed in 1961 for espionage.

But she had “sexual predator” Lonsdale ditched, says Dr Burke, as “she didn’t want to work with him because of his lack of professionalism”.

In the film, the young Red Joan, played by Kingsman actress Sophie Cookson, is seduced by a handler and has an affair with her boss.

The reality is that Norwood was devoted to her husband, who she nursed through liver cancer up to his death in 1986.

Only in 1965 did MI5 get wise to the risk she posed.

Dr Burke explains: “At one time she was vetted again. She was a bit worried so she took an aspirin before going in.

“After that, although she wasn’t arrested, she found she was no longer getting access to confidential material.”

Apart from passing on nuclear secrets, Norwood recruited at least one person to be a KGB spy.

In 1958 she was awarded the Order of the Red Banner, which is given for heroism in combat or long service in the armed forces.

The ideologically driven spy turned down a Russian pension and was never paid for her undercover work.

It was her refusal to get drawn into the “glamorous” side of being a mole, unlike Philby from the Cambridge University set, that allowed Norwood to evade detection.

Dr Burke says: “She was a sophisticated spy. She didn’t draw attention to herself.

“She wasn’t like the Cambridge Five, who courted disaster. She was in control all the way through.”

The extent of Norwood’s betrayal only became clear in 1999 after Russian defector Vasili Mitrokhin opened up his KGB files to MI5 and British journalists.

It came as a massive shock to her daughter and to Dr Burke, who already knew Norwood.

Anita said: “She kept it from everyone. Members of her family didn’t know what was going on at all. It was a terrible shock. We didn’t know what to think.”

Remarkably, Dr Burke thinks Norwood enjoyed her late moment of notoriety.

When he called her to ask if the story was true, she replied, “I’ve been a rather naughty little girl,” then dressed up for the Press camped outside her Bexleyheath home.

Ironically, reporters found anti-nuclear CND signs in her kitchen, where she made chutney.

There were calls to prosecute the granny traitor, but the secret services did not want the details of their failure to come out at trial.

Right to the end, Norwood maintained her belief in communism.

When she was unmasked, she said: “I did what I did not to make money, but to help prevent the defeat of a new system which had, at great cost, given ordinary people food and fares which they could afford, a good education and health service.

“In general, I do not agree with spying against one’s country.

“In the same circumstances I know that I would do the same thing again.”

• Red Joan (12A) is in cinemas now.

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