through the mail order express consignments. >> it's worth pointing out, that bag of flour, that 1 kilogram bag of flour, if that represented $8,000 that could be turned into 1 million pills sold for 20 to 30 bucks on the street per pill. you can see the economic incentives here and why people continue to try and try over again to get this stuff into the united states. keep in mind, what we are talking is not like anything i saw in medical school. it's 100 times more powerful than morphine, which is why it's so dangerous. >> dr. sanjay gupta, thank you. coming up, with arrests expected any day in the mueller investigation, what does it mean for president trump's presidency and the future of the russian investigation? i'll get answers from a former prosecutor next.