With more than 20,000 patients, Dr. Pol has seen it all. Specializing in large farm animals, this senior is anything but retiring as he takes an old school, no-nonsense approach to veterinary medicine.

With more than 20,000 patients, Dr. Pol has seen it all. Specializing in large farm animals, this senior is anything but retiring as he takes an old school, no-nonsense approach to veterinary medicine. Unflappable and unstoppable, this Doc routinely puts in 14-hour days and is a legend in the community. We travel with Dr. Pol across rural Michigan to care for every family pet and head of livestock in need of his expertise.—National Geographic Channel