Don’t miss Dateline NBC on Sunday, Jan 30. BBB and Dateline’s Chris Hansen partner to expose a nationwide air duct cleaning scam.

This Sunday, January 30th at 7pm/6pm CT, Dateline presents a compelling new franchise, "The Hansen Files." With the help of the Better Business Bureau, Chris Hansen and "Dateline's" hidden cameras uncover secrets and scams-- taking a special look into a nationwide ring of air duct cleaning companies. This brazen scam-- one that has thrived for more than a decade-- cons thousands of consumers out of millions of dollars, and targets one of the most vulnerable segments of the population: the elderly. "Dateline" discovers that many air duct cleaning companies across the country are using advertising tricks, such as the infamous "bait and switch," promising a low price for the service, only to raise it once in the door. Using hidden cameras, viewers watch what happens as our volunteers call one of the rogue companies. What you'll see next will surprise and offend you, as these air duct cleaners take our volunteers to the cleaners! But the technician will be in for a surprise when Chris Hansen shows up to expose them.