The NSA is the world’s most sophisticated eavesdropper. It keeps the airwaves safe for Uncle Sam, gathering information any way that it can, mostly through an extensive battery of antennae dishes scattered around the world. The dishes harvest the low frequency signals, the frequency range generally preferred by the world’s military. If atmospheric conditions are right, these can bounce off the biggest dish of all, the earth’s ionosphere. The higher frequency transmissions are trickier, the line-of-sight comms. To patrol this frequency range, the NSA deploys all manner of assets, including a flotilla of spy ships masquerading as ocean survey vessels and, of course, spy planes.

The NSA monitors most frequencies in the radio and microwave spectra around the clock; phone and Internet lines are also filtered. Even general phone communications are regularly sampled. The bottom line is, very little communication escapes the NSA, especially when attempts are made to hide it. If you’re Milly chatting to Maude in the suburbs of Atlanta, Georgia, there’s a good chance the NSA knows your gossip. If you’re a Russian tank commander positioning assets around a Chechen enclave, you can guarantee it.

Occasionally, the NSA picks up transmissions that are only meaningful in the context of hindsight, such as the radio clicks passed between an F-16 and a ground controller in Indonesian airspace in the early morning of Tuesday, 28 April.

Ruth Styles was aware that the Indonesian air force had been particularly active for some time, trying to regain its edge after the recession that gutted the Asian Tiger economies and the subsequent fiscal constraints imposed by the World Bank. Perhaps it was this knowledge that activated the IAE’s personal radar. She had already passed on some recent interceptions from Indonesia to HQ in Maryland. There was something irregular about them. Why? Had she been asked, Ruth wouldn’t have known, but she always listened to her inner voice, no matter how faint its call.

Ruth tried to remember who the analyst for South-East Asia was. Wasn’t it Gioco? Hadn’t she met him at one of the conferences held to foster interdepartmental cooperation within COMINT, the communications intelligence department of the NSA? She tapped the enquiry into the box. The answer was instantaneous. Yes, Bob Gioco: thoughtful, intelligent, hard-working. Unusual name for a black man though, she thought.

Sydney, 2150 Zulu, Tuesday, 28 April

ABC Radio 702: ‘We interrupt this program to bring you a news flash. Qantas Flight 1, en-route from Sydney to London via Bangkok, is missing, feared crashed.

‘Unconfirmed reports are that the 747–400 disappeared from Bali Air Traffic Control radar screens in the early hours of the morning, local time.

‘Just repeating: fears are that Qantas Flight QF-1, the regular service from Sydney to London, has crashed. We will bring you more news on this as developments come to hand.’

Parliament House, Canberra, 2155 Zulu, Tuesday, 28 April

Another uncomfortable silence filled the room. The Prime Minister of Australia, The Right Honourable William (Bill) Blight, glanced at the window and allowed his eyes to focus beyond the raindrops spattering the glass pane. The trees in the grounds of Parliament House had lost most of their leaves, letting them go in a circle of gold on the emerald couch below. Autumn. It occurred to Blight that he didn’t much care for the view. It was sentimental, almost soppy. He preferred the iron trunks of heavy lift cranes that had formed part of the vista of most of his working life, and the ordered ranks of rusting containers that clanged like giant bells when dropped. What the hell am I doing here in this place? he wondered, vaguely aware that the Indonesian ambassador, Parno Batuta, had begun to speak again. Blight blinked, waking from a daydream edged by the oily rainbows that filled the puddles on the docks.

‘Once again, Mr Prime Minister, let me say how sorry I am,’ said Batuta, eyes lowered.

‘I appreciate your authorities informing us so quickly of this disaster. Do your people know yet exactly where the plane came down?’ asked Blight.

‘No. Our military and civil aviation authorities hold different opinions, but no one has had the time to review all the facts. The natural assumption is that the aircraft has come down where it disappeared from radar on the island of Sulawesi. But our military believes the plane could also have flown on outside Indonesian airspace. We are testing both theories. Our air force has pledged every available aircraft for the search and I have been assured that we will find it quickly.’

‘Can we provide any assistance?’