SVU S12 E1 "Locum"
SVU searches for little Mackenzie who ran away from her smothering parents. Their older daughter was kidnapped and vanished years ago, and now they're making Mackenzie look just like her (with plastic surgery and a microchip).
We're talking about SVU S12 E1 Locum with actor Chase Williamson.
This episode takes some cues from the ripped from the headline story of Jaycee Dugard.