The Voyage of the Sable Keech

The Voyage of the Sable Keech is a 2006 science fiction novel by Neal Asher. It is the second novel in the Spatterjay sequence.
The story takes place on the planet of Spatterjay, a world where the oceans are teeming with dangerous creatures and the humans who live there are infected with a virus that grants them immortality.
The protagonist, Taylor Bloc, is a walking dead man who wants to live again and will do anything to get adulation, power and control. An ancient hive mind has sent an agent to this uncertain world.