michael jr. called his parents 12 times on the weekend of the murder. also suspicious, the sloversed a used car lot just one mile from their house. the lot, patrolled by two junkyard dogs, was always dirty and in disrepair. just after karyn disappeared, neighbors said the lot got a makeover. >> michael jr. and michael sr. were seen by the neighbors at miracle motors cleaning up the lot, cutting brush, cutting weeds, burning items. >> was it possible they were trying to remove something connected to karyn's murder? to find out, investigators contacted richard monroe, a well-known forensic geologist. concrete and cinders were found with karyn's body. could he tell if they came from the slovers' car lot? both samples were placed in a scanning electron microscope and hit with high-energy radiation. >> in a vacuum in the sem, the darkness in the chamber, there's no light source. the only light is the x-ray. >> this enables the images of the samples to be magnified up to 5,000 times their actual size. visually, the samples looked similar. monroe then ground the samples into a powder and