A man is sitting in an airliner, which is about to takeoff when another man with a Labrador Retriever occupies the two empty seats beside him.
The Lab is situated in the middle, and the first man is looking quizzically at the dog when the second man explains that they work for the airline.
The airline rep said, "Don't mind Sniffer; he's a sniffing dog, the best there is; I'll show you once we get airborne when I put him to work."
The plane takes off and levels out when the handler says to the first man, "Watch this." He tells the dog, "Sniffer, search."
Sniffer jumps down, walks along the aisle, and sits next to a woman for a few seconds. It then returns to its seat and puts one paw on the handler's arm. He says, "Good boy."
The airline rep turns to the first man and says, "That woman is in possession of marijuana, so I'm making a note of this and her seat number for the police who will apprehend her on arrival."
"Fantastic!" replies the first man.
Once again he sends Sniffer to search the aisles. The Lab sniffs about, sits down beside a man for a few seconds, returns to its seat, and places two paws on the handler's arm. The airline rep says, "That man is carrying cocaine, so again I'm making a note of this and the seat number."
"I like it!" says the first man.
A third time the rep sends Sniffer to search the aisles. Sniffer goes up and down the plane and after a while sits down next to someone. He then comes racing back, jumps up onto his seat, and poops all over the aisle and the seat.
The first man is really grossed out by this behaviour from a supposedly well-trained sniffing dog and asks, "What the hell is going on with this stupid dog?
The handler nervously replies, "He just found a bomb!"