Pamela May Donald, churchgoer, dog-lover, overweight and sweetly naive, is flying from Tokyo to Osaka, "squashed in like a canned ham", when a huge boom echoes through her plane. It drops, "giant hands press down on her shoulders, and her stomach feels like it's being forced up into her throat. Uh-uh. No. This can't be happening. Not to her".

South African author Sarah Lotz's thriller The Three, bought amid a great deal of fuss and for a great deal of money in 2012, has a gut-churningly terrifying opening that is likely to prevent any nervous flyer from boarding an aircraft ever again. Pamela's plane crash is described in full-on, Technicolor detail: "Brace, brace, brace for impact… A rending sound like giant metal fingernails scoring a blackboard… "

But Pamela's flight isn't the only one to have gone down. On 12 January 2012, four commuter planes crash within hours of each other, killing more than a thousand people in South Africa, Japan, Florida and the sea. There are just three, improbable, survivors; children, found alive at three of the crash scenes. They become known as "The Three" and are the subject of intense press speculation, particularly when details start to emerge about quite how odd their behaviour has become.

As global panic about the causes of the crashes spreads, it emerges that Pamela left a voice recording before she died. "The boy watch the boy watch the dead people oh Lordy there's so many... They're coming for me now. We're all going soon." It's been picked up by a horde of evangelical Christians, and they've decided the children are three of the Four Horsemen of the Apocalypse and that the Rapture is nigh.

Lotz has chosen to tell her story in the form of a non-fiction book by a journalist of the ordeal, jigsawing together a mix of interviews, an unfinished biography and even online messages slowly to fill out the disturbing details of what has happened since "Black Thursday" (the End Timers' message catches on frighteningly quickly in her version of America).

Lotz has previously written scary horror as one half of SL Grey, and she is skilled at piling on the dread and the paranoia, as looming black shapes on beds mutter: "How could you let that thing in here?" and as American investigators say things such as: "Listen, Elspeth, this is going to sound as hokey as hell, but [his eyes] started to swim, like he was about to cry, only… Jesus… this is hard… they weren't filling with tears but with blood" (OK, that last one's a bit corny). Amid her creepy children, she is also rather good at comic relief; an evangelical nutjob's website informs followers that the Rapture is close because "the signs are hotting up fast… Plague (rapturesacoming probability rating: 74%)… Thanks to Isla Smith of North Carolina for sending this one through!"

Some of the voices she ventriloquises as Elspeth come off better than others – Paul Craddock, the gay English actor, isn't entirely convincing – but overall Lotz's reportage style works well, as she tangles her readers up with a series of unreliable narrators. It's reminiscent of Stephen King's Carrie and The Three comes preloaded with praise from the master of horror himself. It deserves it: this high-concept thriller is a blast.