When you go to the supermarket and buy fish, you rely on the label to tell you what kind of fish you're getting. Unfortunately, when it comes to seafood, you may not be getting what you pay for. Using cutting-edge technology, we test more than 150 pieces of fish -- everything from halibut to pickerel, sea bass to shark -- bought at supermarkets in Montreal, Toronto and Vancouver. The results? We discover that one out of every five fish is mislabelled, which means many Canadians are being overcharged, left unable to make wise ecological choices, and are vulnerable to food safety concerns. So what does Canada's food safety and labeling regulator, the Canadian Food Inspection Agency, have to say about this? Erica Johnson takes the results of our investigation and gets some surprising answers.