For the first time ever, Toronto Police have seized a drug, 100 times stronger than fentanyl.
It's called carfentanil, and is normally used to sedate large animals.
Police inspectors made the discovery while testing a substance they originally thought was heroin. It actually tested positive for cocaine, caffeine and carfentanil.
Just that drug alone is fatal in small doses and is 10 thousand times more potent than morphine.
It also can't be detected by sight smell or taste.
The drugs is believed to be responsible for 15 deaths in Alberta, and has been found in Vancouver, as well as Waterloo.