'Ah! Mr Shepherd! Are you not coming to join us?' He gave his whiskers a tweak. 'I was explaining about the archaeological remains at Dura-Europos and-'

I kept on walking. I pulled out my BlackBerry and waved it. 'I'll maybe come down later, mate. I've got to make a call.'

There weren't any lifts. The stairway was encased in mustard-coloured walls and a musty, smelly brown carpet that kept me company up all six flights. I'd asked for a room at the top. I wanted the view over the city; I didn't mind what it cost.

I let myself in with a large key. The room was basic, but at least it was clean. There were two sheets and a pillow, a thin green blanket and no TV. A two-litre bottle of water and a small glass took the place of a mini-bar. I used it to clean my teeth each morning, then got the rest of it down my neck before buying another from Reception for the day's sightseeing.

I shoved my earphones into place and hit the icon that looked like a date and time application. It took a second or two to load, and when it did I tapped in Cody's number.

There was a long tone, followed by a short break. Cody Zero One was beginning to receive the call. The green padlock icon on his illuminated screen would be telling him it was in secure mode. He wouldn't have to shove anything in his ear. He'd just press a button and take it on loudspeaker.

Cody Zero One was my new mate in Air Combat Command at Nellis Air Force Base. He was in the CAOC (Combined Air Operations Center) but this was a Coalition operation. The US might be controlling things from Nevada, but it was British boffins at GCHQ who'd contributed the technical and electronics expertise, while the Israelis were providing and flying the weapons-delivery platforms, the F-15s. All three empires were all taking part.

Nellis was about eight miles from the centre of Las Vegas. I knew it well. I'd been there a number of times when I was in the Regiment. We came with RAF Tornado crews to practise splashing targets with lasers so they could come in and bomb them. After a day on the ranges, we'd get down and hit Vegas for as long as we could. Not so much for the gambling – what's the point? – but for the big bowls of shrimp they gave away free to keep you at the slots and tables.