Breaking the Dark : A Jessica Jones Marvel Crime Novel by Lisa Jewell

Meet Jessica Jones: a private investigator and retired super hero based out of Hell's Kitchen, Manhattan, who goes from job to job as a hard living, rough talking, loner.

And then a wealthy Upper East Side woman pays her a visit. Amber Randall is concerned about her twin sixteen-year-olds, Lark and Fox, who have acted and looked very different since they returned from spending the summer with their British father in the UK. She tells Jessica that her children have unnaturally perfect skin for teenagers and have lost all the tics and habits that made them who they were.