preserved with a substance called denstone. >> kind of like pancake batter. then you're able to lift those impressions and bring them back to the crime laboratory. >> inside though home, investigators lit the hardwood floors from various angles and saw two more sets of shoe impressions. criminalists lifted the prints with gelatin strips. >> you roll the gelatin with the black side down on to your questioned shoe impression. and when you peel it off, the adhesive in the gelatin adheres to the dust particles on the floor. >> with some research, investigators identified the prints outside as a pair of size 10 nike air jordans. the perpetrators inside also wore nike shoes. one wore the air medal force model, the other the shocks trainers.