Thomas smiled, looked out the passenger window. Night had fallen. An eighteen-wheeler towered over them, and he found himself peering past the running lights into its grime-greased recesses: the roaring wheels, as tall as his door; the black-iron linkages, clacking to the bounce and grind of impossible loads; the pavement, rushing like a crimson river beneath the tractor's taillights. He looked away, overcome by a peculiar sense of vulnerability, as though he had leaned too far over a balcony railing. All he needed to do was reach out his hand and he would be yanked from the world, stamped and spun into dripping oblivion.

'I don't know what to say,' he replied, scratching his eyebrow. 'I mean, the book got me tenure, but it was one of those things that only seem to impress the people who already know you. Hopes were high. The reviews were harsh. It went out of print.' Now it's little more than a joke passed down through generation after generation of graduate students.'

'Bible's Bible,' Sam said.

Thomas would have laughed, but there was a note of genuine pity in her otherwise rueful tone. 'What do you mean?'

'That's what they call it. The grad students at Columbia.'

'You've been interviewing people about me?'

Sam looked at him for what seemed a perilously long time, given her 80 mph cruising speed. A conspiracy of lights from the HUD and the dash made her seem almost supernaturally beautiful. Shining lips. Swales of blue and yellow along her cheek and neck. Suddenly the truck's headlights flashed through the rear window, bleaching all the inviting tenderness from her look. For an instant, she seemed more statue than human, with wet marbles for eyes.

'This is for real, professor. You do understand that?'

'It's starting to sink in,' Thomas replied.

Her gaze clicked back to the floating corridor of taillights before them. Several moments passed in encapsulated silence.

'So why the sudden interest in my book?' Thomas finally asked.

Sam shrugged. 'Because I find it curious.'

'Find what curious?'

'Well, the Argument is actually yours, not Neil's.'

Thomas snorted through his nose. 'Not anymore.'

'Why's that?'

Thomas frowned and smiled. 'Maybe someday you'll have kids.'

Sam laughed and shook her head.

'What's wrong with that?' he continued. 'A gun-packing momma. For a single-parent divorcee like me, it doesn't get much hotter than that.'

Sam beamed, but continued shaking her head. 'What did you make of Mackenzie's question?' she asked, obviously trying to change the subject.

Thomas studied her for a mischievous, tongue-against-the-teeth moment. 'Which one was that?'

'About the Argument. I mean, he is right, isn't he? Why would Neil bother making the Argument if there's no chance of convincing anybody?'

'Yeah…'

'You don't sound impressed.'

Thomas shrugged. 'It's a perfectly reasonable question.'

'And that's a problem?'