Bringing The Sniffer

FBI knew that their investigation was going really slow and they had no possible leads. They brought in a sniffer dog to see if left any smell behind that inside the tunnel that could help them in catching the culprit. The dog caught some smell, made his way through the trenches, the dog led them to an empty space because there was nothing except the smell which was caught by the dog’s nose. Still, no success in the investigation the team was getting frustrated. They had to do something before the culprit flew away from the city.