The Sentience Machine - The Rik Sylver Sci-Fi Thrillers, #2

The Sentience Machine is the sequel to The Credulity Nexus, a fast-paced, science fiction thriller set at the end of the 21st century. Two years have passed since PI Rik Sylver became involved in the credulity nexus affair and things are looking up for him - until his old nemesis, Rivers Valdinger, shows up with a message from Omega Point. Rivers is a "zombie" - the mind of a dead human uploaded into a powerful robot body.
Omega Point is a "ghost farm" a satellite, orbiting the Sun, with the disembodied minds of 20, 000 dead rich people living inside its virtual world. The message Rivers brings is that Omega Point is under attack by an unknown enemy and Martin Lanham, the uberghost who runs Omega Point, is holding one of Rik's friends hostage until Rik finds out who the culprit is. Once again, Rik and Rivers become unlikely allies as they track down the perpetrator.
Once again, they quickly find themselves tangled up in a web of lies and misdirection, prejudice, deadly danger, and high-level corruption, as they stumble towards a discovery that neither of them could have foreseen.