nique leili was dead.emingly happy mom was violent >>> welcome back. and craig melvin. nikki lyerly was dead, and now, her husband was telling police that this seemingly happy mom was violent, and often mentally unstable. investigators were about to get a better view into that home than they would ever imagine. here again is dennis murphy, with the house on sydney's cove . >> reporter: within minutes of finding nikki's body, police raced to the lyerly home, about a mile away. what they observe right away was astounding. the home security system that matt lyerly had casually mentioned to detective emerson a few days earlier appeared more appropriate to ft. knox them a house in the burbs. >> when you first see the house in the road, you can see all of these cameras on the eaves of the house, both sides. >> reporter: there were 21 security cameras in all, with a tricked out control room to monitor and record everything. >> he sounds like a one-man nsa ? >> he was in a very low crime area, so, it almost boggle