risk. it's one of the chief ways drugs and other contraband can be smuggled into the jail. at new york city's riker's island we found the correctional staff wasn't about to let that happen. >> welcome to new york city department of corrections. my officer p hunt, i'm a member of the canine unit, narcotic unit. today we're going to do a narcotic serve where we board the bus and looking for any type of illegal substance, crack, cocaine, marijuana, heroin. if you have it, people, now is the time to put it on the floor or see that amnesty box, deposit it in that box over there. >> when leaving the bus to enter the jail facility, visitors are not only given a blunt warning about contraband, they're handed a number to correspond with their seat. then a drug sniffing dog boards the bus. >> my dog boards that bus and starts scratching seat number 3. i'm going to look over and see that's who we must search. >> got balloons. >> beautifulment. >> right here, we found two