In the one conversation we’d had since she released the book, she’d told me it had nothing to do with the money. That the amount she had made was just as much a surprise to her as it was to me. It had been an accident, our meeting that day—she’d been standing in a queue for coffee at Kew Gardens, wearing skinny jeans, tan ankle boots in leather as soft as butter and a simple white T-shirt, hair tied back in a sleek ponytail. The epitome of the laid-back casualness I could never get right, even though she was my mirror. Actually, she’s not my mirror. Some twins are real mirrors: one left-handed and one right, a smatter of freckles on the right cheek for one and the left for the other.

But Leah is me.

My perfect twin.

Although we are so different in how we think and act and choose to spend our free time. Yet despite being so different in our tastes, we have always ended up with the same haircut. In an act of rebellion after the Michael incident, I had cut mine into a bob. At the same time, across town in a different hair salon, Leah was having exactly the same thing done. She had said it was to prove to me that she wanted people to tell us apart, that she would never again cross the line like she did with Michael.

Did Chris think it was me in the blue underwear?

Surely my own husband would have known it wasn’t me? Surely Leah wouldn’t be able to pretend to be me to the man I had married? To the man who had promised to love me to the moon and back in front of everyone?

But if he knew it wasn’t me…

Why would he have done it? And how? They had never met, my husband and my twin. I met Chris a few months after the book was released. He had approached me on the train as I traveled home after work.

“Are you who I think you are?” he had asked. I’d shaken my head and turned away to continue to sip a slightly warm gin and tonic in a can. A treat to myself after a hellish week.

“Are you the other one?” he had asked, ignoring my obvious signals for him to leave me alone.

Eventually, I had acquiesced and looked at him. At his chocolate brown eyes and the little creases around them as he smiled. I had been about to say something rude, but suddenly I was scraping around my head for something witty as my traitorous mouth inched toward a smile at the stranger. “Guilty as charged,” I’d said, wincing at how ridiculous I sounded.

“Of not wanting to drag your family through the tabloids?” He slid into the seat opposite, digging one hand into the backpack on his lap to fish out two tins of a slightly more salubrious brand of gin and tonic. “Beverage?” He waggled one at me. Chris has this habit of grouping things together with a common word: so any alcoholic drink is a “beverage,” although which drink he is referring to is denoted by time of day, location and company; conventions strictly adhered to but known only to a select few. “Snacks” is the common name for any savory—they must be savory to count—item consumed in front of the TV. Any meal containing bacon is “breakfast,” irrespective of the time of day the meal is consumed, unless it’s a burger with bacon because that is obviously not breakfast. We have added to his dictionary over the years. “Telly” is anything mind-numbing that you can watch without attention, “hols” the kind of trip where the location is less important than the presence of sun and cocktails. I thought this one was endearing the first time: walking hand in hand through the terminal at Gatwick, dreaming of our swim-up room at an all-inclusive resort in Turkey, as he sang a song about how we were going on “hols” and all the fun we would have. Now the word kind of makes my skin crawl, if I’m honest.