The plot loosely follows: Martin Blom is shot in a parking lot and wakes up blind. He is diagnosed with Anton's Syndrome, an actual (!) medical condition "caused by damage to the occipital lobe which extends from the primary visual cortex into the visual association cortex".
In other words, Martin believes he can see during the night, and that his doctors have been lying to him about his 'special case'. He escapes the hospital and engages himself on a search for his missing girlfriend, a search that will lead him to confront himself and a secret even more devastating than his own.
The book is written entirely in the first-person POV. Given that the person narrating the story believes he can see, while the reader knows- possibly- that he can't, lends a sublimely horrific yet sympathetic tone to the protagonist's voice. After all, Martin is the only person in the book we can trust, given that events are related from his hopelessly skewed point of view. Or are they skewed? The beauty of the choice of POV is that the reader has no choice but to fling themselves headfirst into the dream-like tunnel of Martin's delusions (if that is what they are) as he attempts to solve the mystery of his girlfriend's disappearance and of his own affliction.
The descriptive level of the book is surreal and terrifyingly subjective. It makes the reader feel like they are walking in the dark, and one wrong step will send you plunging into the darkness lurking at the edges of the narrative. There are many sub-stories swimming around here, some of which may be true and some not. You get the feeling that they are all, in some way, true- you have to believe Martin, and no matter how hard you try to distance yourself from his version of the 'facts', he still manages to induce both pity and awe as he leads you deeper into his own complex tale of paranoia and conspiracy.
'The Insult' is not a noir. Nor is it mystery, drama, thriller, science-fiction, black humour, or the sort of bizarre amaglamation of sex and circus performers that John Irving is so fond of. It both combines and transcends all of these traits, and ends up becoming, at its core, a conspiracy. It's a conspiracy against the reader's senses, and one that's a pleasure to willingly throw oneself into with cheerful abandon. Once you're in, though, tread carefully- from start to beginning, you'll be flying blind, with only Martin Blom and madman Rupert Thomson as your guide.