Pineapple Express (2008)

Lazy stoner Dale Denton has only one reason to visit his equally lazy dealer Saul Silver: to purchase weed, specifically, a rare new strain called Pineapple Express. But when Dale becomes the only witness to a murder by a crooked cop and the city's most dangerous drug lord, he panics and dumps his roach of Pineapple Express at the scene. Dale now has another reason to visit Saul: to find out if the weed is so rare that it can be traced back to him.

Official website: http://www.sonypictures.com/movies/pineappleexpress/