Moonlight Mile by Dennie LeHane

A gritty mystery featuring a husband and wife team of private investigators, Kenzie and Gennaro.  This is the sixth in a series by Lehane. The team is asked to search for Amanda McCready, a sixteen year old who has gone missing.  The twist is that Amanda had been kidnapped at age four, found by the investigators, and returned to her neglectful mother.  They take up the new search at the request of Amanda's aunt, who had kidnapped Amanda at age four to remove her from her mother's negative influence.  The search leads them into the underworld of Boston, peopled with identity thieves, meth dealers, crime bosses and the Russian mafia.  Plenty of plot twists, including a second disappearance of one of Amanda's friends, keep the plot moving to its violent conclusion.  368 pages