When forensics professor Gideon Oliver joins an Amazon
riverboat expedition with a group of research botanists, he
expects a nice vacation. What he gets is heat, corrupt
officials, dangerous insects and animals-and worse.
As they travel upriver, one of the botanists is killed by a
deranged passenger who leaps overboard and flees into the
darkness. No one can explain why. Theories begin to simmer,
and stories of long-past, half-forgotten grudges-and new
ones as well-boil to the surface.
Only when a fresh skeleton turns up in the river, scoured
to the bone by voracious piranhas, does Gideon realize that
in this jungle full of predators, humans may be the
deadliest of all.