Thousands of dogs are ill or dying across North America and it's been going on for years. No one can say what, exactly, made the dogs sick. But owners say they fed their dogs a seemingly harmless product: a popular chicken jerky treat. There are warnings on both sides of the border about the treats, which are made in China and marketed by some of the biggest pet food companies. But there is no definitive link between the treats and the illness. And there have been no recalls. Tom Harrington is on the trail of the mysterious illness, putting the treats to the test, and asking questions about a product that is not regulated in Canada. We ask: when things go wrong, who is fighting for Fido?