Monday, Aug. 10: The Pensacola murders

It was the kind of headline some people needed to hear twice to make sure they'd heard it right: A mother and father - parents to 17 children, including 13 who were adopted - murdered in their home. Nine of those children - all with special needs - were in the house at the time. Within days police arrested a group of suspects, and established a possible motive. But there could be much more to this case then meets the eye.

NBC's Keith Morrison brings you the latest on this heart-breaking mystery at 10 p.m. ET, 9 p.m. CT on Dateline Monday.