it all checked out as that local woman, nicole pietz, who had been missing for a week. e diamond tennis bracelet she always wore was not on her wrist, but police were confident enough in their tentative i.d. to pay a visit to nicole's husband, david. and the information david pietz would soon share with detectives about when his wife was last seen and what she left behind would be critical to the case. >>> coming up -- but it was something that was missing that turned out to be even more important, and puzzling. >> there's no indication that anyone else had been behind the wheel of nicole's car. >> when "dateline" continues.nus ♪ check in from afar with remote access, and have professional monitoring backing you up with xfinity home. demo in an xfinity store. call, or go online today. >>> with a great many bad days, one of the worst ones had to be the day she was found. >> oh. i'll never forget that as long as i live. >> found strangled. >> it came over the tv that a body had been found and we just knew that it had to be her. >> had to be your nici. >> yeah. >> nicole pi