Usually, it’s the spy pretending to be the ordinary family man.
But in this case, it was a conman and serial bigamist claiming to be a ‘secret agent’ as cover for his infidelities.
Mary Turner Thomson, 53, from Edinburgh, thought she had found the perfect man when she met her husband online.
He seemed kind, caring, attentive and a wonderful father to their two children – and she believed his claim that he had to spend long periods away as he was a CIA agent.
It all fell apart when she discovered he had another wife and at least 13 children with six women.
Mary said: ‘I met William online when I was a single mum with a nine-month old baby.
‘He was very charming, and we sent emails back and forth before meeting up about two weeks later.
‘After six months of being together I fell pregnant, which was a huge surprise because he told me he was infertile after having mumps as a child.
‘l thought he was going to think I’d had an affair because he was so utterly convinced he couldn’t have kids.’
Lying about his fertility was just the start.
Time spent away on missions provided the perfect cover for seeing his other families.
It also meant he could demand ransom money, persuading Mary to part with almost £200,000 to pay blackmailers who, he said. had threatened to kidnap their children, Robyn, now 19, from a previous relationship. Eilidh, now 16, and Zach, now 13.
She said: ‘By this stage, I was four years in and completely under his control, so l sold everything I owned – my house. my car, my life insurance, everything.
‘It was a feeding frenzy and, once it started, there was just more and more and more.
‘I thought if we didn’t give them money, they would kill the kids. I was living in abject terror.’
Mary described how her life mirrors TV’s Mrs Wilson – who discovered her ‘spy’ husband had three other wives.
The acclaimed TV drama, which finished last week, was inspired by the true story of war-time ‘secret agent’, bigamist and serial liar Alexander Wilson.
Mary said watching the drama was like seeing her own life played out on screen.
Of course, there was no blackmailer, no undercover missions. and no threat on her children’s lives.
Mary discovered the truth when she received a call from another woman claiming to be the real Mrs Jordan.
‘William’s other wife phoned me in April 2006 and asked, ‘Are you also Mrs Jordan?’ I said yes, and she replied. ‘Well I’m the other Mrs Jordan’.
‘We met in a café and talked for about 12 hours. When she left at six in the morning, I sent him a text and dumped him. I thought that was appropriate.
‘He tried for months to persuade me, but there was nothing he could say that would ever suck me back in again.’
William has been jailed for bigamy, illegally possessing a stun gun, fraud, and other offences.
He served two and a half years of a five-year sentence, and was deported to America on his release.
Mary said: ‘Within six months I was contacted by a pregnant lady who had lost her home because he convinced her to come live with him.
‘He changed his name and I didn’t hear anything for three years. Then I was contacted by a lady, who is quite like my American counterpart.
‘She carried on dating him after she found me, and I helped her set up hidden cameras in her home.
‘We set up a police sting and he was arrested, and spent another three years in prison in America, from 2014 to 2017.’
‘We think he averages about six women at a time.’
Mary documented her story in her book, ‘The Bigamist: The True Story Of A Husband’s Ultimate Betrayal’.