‘Time was running out when he had at last succeeded in cracking the safe…’

In an exclusive extract from his forthcoming memoir (being published posthumously), Cynthia’s spy handler recounts how the pair stole naval codes, which would later help the Allies land successfully in Vichy-controlled French north Africa

As I walked into the room, I encountered the faint scent of an expensive perfume. Cynthia stood up, smoothing down imaginary wrinkles in her impeccable skirt, to greet me with a handshake and a smile.

She was wearing a cream silk shirt and jacket with a skirt shorter than what passed for normal at the time, barely covering her knees and not covering them at all when she crossed her legs. Careful make-up, blonde-ish hair and wide-set eyes completed an extremely attractive picture.

She was very nervous. Did I mind if she smoked? Of course not. I leaned forward with a lighter as, with a slightly trembling hand, she placed a cigarette between her lips.

‘I think we might have something for you,’ I said.

‘That would be wonderful,’ was the reply. No longer nervous, she was glowing with excitement. A few days later, at my request, she was back. I explained that a key task assigned to me was to target the German, Italian and Vichy French embassies by whatever means we could. I wanted her to help with this… ‘Leave it to me,’ was her confident reply.

[We received] instructions to do whatever we could to help get hold of the Vichy French naval codes, a demand that became more urgent after the United States entered the war, as thoughts started to be entertained of a possible landing by the Allies in Vichy-controlled north Africa.

Cynthia started at the top by asking, as a reporter, for a meeting with the French ambassador, who however, turned out to be the most unpleasant kind of Vichy supporter. But the meeting had been arranged by the press attaché, Charles Brousse. Before long, she was getting on famously with him. A minor nobleman on his third marriage, he regarded himself as an expert on food and wine and, by extension, women. Twenty years older than her, he had won the Croix de Guerre as a pilot, flying over the German trenches in the First World War.

The problem was that Charles could tell her all about gossip in the embassy but had little access to any sensitive information, let alone the codes.

By this time, Charles was thoroughly disillusioned with Vichy… [He] was quite wealthy in property in France but had little in his US bank account. Cynthia, who by now had told him that she worked for US Intelligence, offered him a monthly subsidy.

She asked Charles directly for his help in acquiring the Vichy French naval ciphers. His objections were purely practical. They were so well protected that he considered it impossible. But he provided Cynthia with details of the layout of the embassy.

We had ruled out the idea of a burglary as too difficult as the embassy at night was patrolled by a security officer. But Cynthia said that if the operation had a really competent burglar on their books, she would like to discuss the problem with him.

Cynthia was introduced to an American burglar who claimed to be at the top of his profession. He warned, however, that unravelling the combination to a well-protected safe required patience. It could take hours; and he would need to crack the combination to the door to the cipher room as well as that to the safe in which the books were held. More time would then be required to photograph them. How was this to be achieved when the embassy was constantly patrolled?

It was Cynthia who came up with a solution. Her plan was for Charles to tell [the guard] that he was having an affair with her. This had to be conducted very discreetly, as he was still married. He proposed to bring his lady friend, plus champagne and a light meal, into the embassy after hours. They would have supper in the embassy’s waiting room [close to the corridor leading to the cipher room], which conveniently had a large divan. If the security guard would cooperate, he would be well rewarded by Charles.

Charles agreed to try this, taking Cynthia to the embassy well after hours, having forewarned the guard. The guard, keen on the promised reward, stayed away from the entrance area and waiting room. This stratagem was repeated on a second occasion.

On their third assignation, the burglar entered the building admitted by Charles. Cynthia guided him to the steel door of the cipher room. There followed over two hours of tension as he struggled with the combination. When this finally was mastered, he showed Cynthia how to unlock it in future, then attempted to unlock the safe. Time was running out when he had at last done so. There was no time to photograph the cipher books and they then had to withdraw.

[On the fifth attempt] Charles once again told the guard in advance that he must not be disturbed. The burglar was let in through the window to the waiting room. But Cynthia’s instinct told her to take some additional precautions. While the burglar worked, this time quickly, to open the safe, she stood at the entrance to the waiting room… and removed all her clothes, ending up wearing only her pearls and high-heeled shoes. She also told Charles to get partly undressed.

It was just as well that she did, as the watchman suddenly appeared, waving his torch around. Having caught a glimpse of her undressed – and, in a real, not simulated, panic, exclaiming ‘Oh la la!’ – he switched it off with profuse apologies and left.

The books were dispatched to be photographed. With Charles and Cynthia in a state of high anxiety, they were not brought back until 5am.

The negatives of the copies of the code books were handed over to US Naval Intelligence and dispatched to Bletchley in the care of a King’s Messenger on an RAF aircraft. I received effusive thanks from Dilly Knox and congratulations from [celebrated senior spymaster William] Stephenson, for both of whom Cynthia by now had achieved legendary status. The landings in north Africa took place at the end of the year, aided by the signals intelligence to which Cynthia had made a decisive contribution, as the naval codes she had acquired enabled the instant deciphering of the messages sent to and from the Vichy forces in north Africa. The intercepts had revealed the state and dispositions of the Vichy naval defences, the crumbling of the Vichy defenders’ morale, and the precise moment at which they might be prepared to sue for peace.

Cynthia was told formally that her efforts ‘had saved a lot of Allied soldiers’ lives’ [and described as the] ‘greatest unsung heroine of the war’.

And yet she was still not considered ‘respectable’. Even her friends regarded her as unscrupulous, which she [took] as a compliment, given the cause she had served.

Cynthia had signed up to do as much damage as she could to the Germans. Respectability had nothing to do with it. It was true that she was by nature an adventuress. She loved the sheer excitement of spying and of being a femme fatale.

Yet she had principles which she would never compromise. Her success as a secret agent came not just from her looks and intelligence but from a determination to do as much damage as she could to the Nazis… and stop at nothing in doing so.

Abridged extract from A Spy Called Cynthia. Note from the book’s editor, Robin Renwick: ‘Cynthia’s family were adamant that she did not have an affair with the author… Whilst I cannot vouch for the personal aspects of this story, I can guarantee the accuracy of this account of the exploits of Cynthia as a secret agent of British intelligence in the war.’