How can you trace the life of a man with 23 fake names? Carolinda Witt did, uncovering the truth about her grandfather's life as an internationally hunted conman and brave double agent.
She also managed to reunite a large family separated by his lies.
After Carolinda's mother Effie died 10 years ago, she began searching online for her extended family in England.
Effie already had secrets in her family: she had been told in her 20s that the woman she knew as her mother was actually her grandmother and her birth mother was her sister.
At that stage the identity of Effie's father was unknown — only a fake name on her birth certificate and the rumour he was a "stage-door-Johnny" who met her mother at the theatre.
A week after Effie's death, Carolinda found a man who said he had been looking for her. Mike Adair claimed to be her cousin and said they shared a grandfather, named Walter Arthur Charles Dicketts.
It turned out that despite being told she was an only child, Effie had one brother (who was given up for adoption) and another four half-brothers: her father had married four women and had two mistresses, one being her mother.
Effie had married in England, before starting a new life in Nairobi, Kenya, with her husband.
A world away, Carolinda grew up not knowing the truth about her grandmother, who she'd met only a handful of times.
From family drama to spy mystery
It was too much to take in at first.
"Ten days after mum's death, it was a big ask for me to deal with," Carolinda said.
A year after that first online chat with her cousin, Carolinda flew to Britain to meet her new family and put straight the past untruths passed down through the family.
Next, Carolinda decided it was time to deal with her grandfather.
She hired a researcher to have his files sent to her from the British National Archives.
"Then I started to get into the spy thing," she said.
Walter served in the Royal Naval Air Service and the Air Intelligence division of the Air Ministry in World War I.
But he had also been charged at least nine times for various fraud-related cons, usually involving forged cheques with fake names. He had been extradited from Austria and hunted by police for eloping with a 16-year-old girl.
His criminal record meant he couldn't re-join the RAF or intelligence services. But Carolinda said it, along with his powers of persuasion, made him a perfect double agent candidate.
No honour among thieves
Walter had an unusual introduction to MI5 and his role as a double agent.
He had become friends with a man named Arthur Owens after meeting him in a small Richmond bar, west of London, in March 1940.
British intelligence expert Nigel West said Owens was a pre-war spy working for both Germany and Britain. He is now known as MI5's first double agent, codenamed Snow.
It didn't take Walter long to suspect his new friend was a Nazi sympathiser. He decided to hand him in to MI5.
"When he originally encountered Snow he was so horrified by a man whom he believed to be an authentic German spy, that he reported him to the authorities," Mr West said.
Documents show when Walter went to report Snow, MI5 thought his position as Owen's friend was useful and decided to employ him to watch an oblivious Snow.
Snow had been imprisoned at the beginning of the war after it was discovered he was supplying information to both Germany and Britain.
One of the conditions of his release was to cooperate with MI5 and use his contacts within Germany's military intelligence service, the Abwehr.
'Into the jaws of lions'
Walter was now known by MI5 as his codename "Celery". His first job was to visit aircraft factories around the English countryside posing as a German spy to expose flaws in domestic security.
After six months Walter volunteered to go to Berlin with Snow, posing as British traitors, to build a relationship with Snow's contacts.
Walter underwent five days of interrogation by the Abwehr which involved being drugged, plied with alcohol and offered women in an effort to expose his allegiances.
"The principal mission was to sustain the myth of both of these men being willing Abwehr agents going to Germany when they had no necessity to do so," Mr West said.
After he gained their trusted, Walter was able to establish himself as a conduit to the Germans.
Mr West said what he achieved was incredible.
"It's all very well being a double agent from the safety of allied territory, but there are only really three examples of people who put their lives at risk by going back, putting their heads into the jaws of the lion," he said.
MI5 abandons Celery
It wasn't until Walter returned to England nearly a month later (the Germans had sent him to ferry spies into Britain) that he learnt Snow had betrayed him.
Snow had not only told the Abwehr that Walter was a double agent, he had told MI5 that Walter was a traitor who had really defected to the German cause.
"When they came back they separated and interrogated them so they couldn't swap notes," Carolinda said.
Both Walter and Snow had numerous interrogations with MI5 as their stories differed.
"What transpired thereafter baffled the greatest minds in MI5," Mr West said.
"It's the conundrum, what was the true loyalty of these two men?"
After one joint confrontation, the majority of MI5 believed Walter's story and Snow was imprisoned until the end of the war.
Though MI5 went on to employ Walter for two subsequent missions up to 1943, official records didn't explicitly say he was innocent.
Clearing his name
After retiring Walter was involved in a scam and imprisoned for two years before his death in 1957 of gas poisoning.
After finding out her remarkable family history, Carolinda decided to write a book, Double Agent Celery: MI5's Crooked Hero, driven by her determination to clear her grandfather's name officially.
"It was obvious to me that Celery was innocent but I had to prove it once and for all," Carolinda said.
Mr West said one thing missed by some who study the Celery case, is the extraordinary bravery of his work.
"In my opinion it is paralleled only by one other double agent during the whole of the Second World War," he said.
Carolinda said the tragedy of the story is that Effie would never know the truth about her father's unbelievable life or the existence of her siblings.
"The saddest thing is that I couldn't tell her," Carolinda said.
"So I'm pregnant with this information and I can't share it with Mum."