After checking the cable connection on the laptop, she plugged the one-time digital key into a USB port and entered her code. A small window appeared on screen, a progress bar. It moved painfully slowly as her machine reached out through a dedicated fibre-optic link to the National Intelligence Agency server at Cerner, from where her comms protocols were forwarded as flash traffic across the Vancouver Alliance military satellite network on a stand-alone channel dedicated to Echelon data.

Thousands of miles away, on a scarred kitchen table that had entered its second century the year Queen Victoria ascended the throne, another laptop encased in its own formidable digital armour shook hands with hers. A second later her husband winked into existence on the screen in front of her. He was holding the baby, asleep, against his shoulder. Caitlin’s heart lurched when she saw how much Monique had grown. She was a baby no longer.

‘Oh, honey, oh my God! Look how big she is! Is she walking yet?’

Her question was accented with a faintly distressed note. The child was living another life, growing up in a world far removed from the one in which she moved. Caitlin was not an automaton, but, while familiar with fear, she had learned to control it. Fear was a variable, something to be used. But now she felt fear as a runaway horse. Her daughter was growing up without her, not knowing her. Caitlin’s stomach clenched. What the hell was she even doing here, playing charades and dress-ups for Jed Culver? She should’ve been at home.

‘Not walking, no,’ smiled Bret, who hadn’t picked up on her sudden spiral into maternal shame and panic. ‘But it won’t be long before she’s crawling, I reckon. I’ve already moved everything up off the bottom shelves.’

And what had Caitlin done while Dad had been readying the family home for the day their daughter was able to crawl off her play mat for the first time? Killed half-a-dozen men down in South America, that’s what. Some of them undoubtedly fathers like Bret.

And now she had assumed yet another identity, preparing to infiltrate a potentially hostile regime on the soil, the scorched earth, of her homeland. Or was it her former homeland? She couldn’t be sure of anything now, other than the pain she felt just under her ribs when looking at her husband and child.

‘And how are you, honey?’ asked Bret. He knew better than to ask her any specifics about where she might be, what she was doing, or even when she might be home. The reassuring banalities of everyday life, the cushion of normality on which the relationships of real people rested. But not Caitlin Monroe’s. He had no idea he was talking to Colonel Katherine Murdoch, for instance. He had no need to know.

‘I’m a little tired,’ she said. ‘Been moving around a bit with work.’