Ming Flanagan's been waxing lyrical about it for years and Snoop Dogg/Lion is forever singing its praises, but how does the legalisation of marijuana for recreational use really affect a community? That's what clinical psychologist John Marsden wants to find out, so he heads to Denver, Colorado to see how it works for them. High school students tell him that getting stoned is now more socially acceptable than drinking alcohol and he learns the drug is already the number one reason why teenagers enter residential programmes for addiction treatment. Sounds interesting to say the least.