so i've got a phone call from the tiki lodge. i can't identify what room it came from. >> the motel had 30 rooms. almost all were occupied on the day of the murders. detectives began the painstaking task of trying to identify all of the tenants. >> for the most part, it was people just passing through. the registration cards didn't have date of births, so you're looking at very common names. >> and most of the hotel guests paid in cash. another dead end. so investigators had to return to the scene of the crime in the hopes they might have missed something. it doesn't operate out of basements or back alleys. it grows more sophisticated every day. if it were a business, it would be a fortune 500 company. fraud has evolved. american express intelligent security gives you tools to fight fraud and a global service network that never stops working. so you can be a member of a more secure world. this is what membership is. this is what membership does. >>> based on the evidence, police suspected that their killer called real estate agen