Public relations consultant Amber, airport load operator Louis, make-up artist Chanel and supermarket worker Troi talk frankly about their casual cocaine use and learn more about the wider effects of their favourite drug. Amber and Louis submit samples to a Home Office narcotics laboratory to learn what is actually in the white powder they snort, while in Colombia, they leave the safe tourist trails and come face-to-face with a cartel assassin.
Troi and Chanel witness the unsanitary conditions under which cocaine is made, and discover the ingredients that go into the drugs they routinely use. Louis encounters a cocaine smuggler and Amber accompanies armed officers in the Colombian Navy on duty.
In the final episode, the four casual cocaine users discover the effect Colombia's super-strength is having on users in Britain, from an increase in first-time addicts to a sharp rise in overdose deaths. Will they continue to take cocaine for fun?