 The plot was simple, a couple are murdered when they where about to move, but specifically when they are about to sell a truck. A driver s license appears to be the big clue, but its just a real-life plot twist. Instead, the murderer is all about stealing the truck and planting false leads. He is an ex-con, who was very careful, but after 9 months of trailing him, he left a wooden or plastic spoon in the trash, which law enforcement recovered, tested the saliva and got the match they were looking for, hence the title. I can tell you the most expensive part of filming was the truck, which was rather unique and cost the company plenty to even find one, let alone the exceedingly high rate the owner charged to allow it up from Florida for filming.