On NBC's The Biggest Loser, trainer Jillian Michaels tells people what to do — and gets results. But one little guy who won't listen? Her 14-month-old greyhound mix, Seven, who goes crazy when Michaels rides her horse, Buzz. Worried that Seven may one day be hurt or killed by Buzz, Michaels calls on Dog Whisperer Cesar Millan for help. Check out our sneak peek above, and be sure to watch the full episode of the Dog Whisperer — featuring Michaels's plight and two other stories — tomorrow night, Nov. 6, at 9 p.m. ET on the National Geographic Channel.

More about the Dog Whisperer on PEOPLEPets.com:
5 Things You Didn't Know about Cesar Millan
EXCLUSIVE! At Home with Cesar Millan