Within Without: A Nyquist Mystery by Jeff Noon
In the year 1960, private eye John Nyquist arrives in Delirium, a city of a million borders, to pursue his strangest case yet: tracking down Oberon, the stolen, sentient image of faded film star Vince Craven. As Nyquist tracks Oberon through a series of ever-stranger and more surreal borders, he hears tantalising stories of the Yeald, a First Wall hidden at Delirium's heart. But to get the help he needs to find it, he'll have to journey into the fractured minds of the city's residents, and even into his own... File Under: Science Fantasy [ Go Fourth | All Mad Here | Uneasy Dreams | Borderline ]