Mindstar Rising by Peter F Hamilton
Mindstar Rising was Peter F Hamilton's first novel, and the first in the Greg Mandel series, first published in 1993. It's set in England in the not-too-distant future, post sea-level rise, post credit crash, post Socialist Republic. Post civil war.
Greg Mandel is an ex-army officer, with army-supplied implants which release neurohormones to enhance natural empathy. It allows him to read moods easily, detecting guilt, fear etc from the most poker-faced opponent, though to some he's just a psychic freak. It seems like a natural move to set up a private detective agency, and when a high-profile company hires him to help unearth a saboteur, Greg looks like he's about to get a serious reputation-boost.
Nothing is ever that simple, though, and before long he's caught in a web of industrial espionage, politics, and personal vendettas, involving the ultra-rich, street gangs, and lone hackers. Who can you trust, and what happens when you and those around you start placing too much faith in your psychic abilities? Unexpected alliances form, and help comes from unlikely places when mistakes are made.
The tension builds nicely through the novel; I was practically biting my nails for the last 40 or 50 pages. Although Greg's a private detective, the central part of the story isn't so much him working out what's going on (I'm not sure I even quite followed the logic of what had apparently happened, it was a bit convoluted) as how he deals with it and what the consequences of the investigation are. There are some interesting characters in there, not least Greg himself, who of course is a man with a shadowy past which eventually comes to light. The setting is well-described, it feels believable and is given a kind of concrete reality by mention of turning off the B557 (or whatever it may be) to some small market town (how I do love the fact that it's set around Rutland).
If you enjoyed Neuromancer, or Mad Max, or V for Vendetta, there may be something in this novel for you; or if you like your sci-fi a little grubby around the edges, and are cynical about politics in general.