Fever Season by Barbara Hambly

Benjamin January is back in this sequel to A Free Man of Color.  It's summer and those that can afford to have traded the heat and sickness of New Orleans for the coolness of Mandeville by the lake.  The poor slaves and freed folks left behind are starting to disappear.  Benjamin is asked to find out where they've gone.  Have they died from cholera? Have they been hijacked and sold up the river? Another engrossing story of early days in New Orleans! 336 pages.