Synthetic designer drugs are flooding into the U.S., mostly from China. They are being sold to younger and younger teenagers. Colorado health officials are investigating three deaths, to determine if they are tied to a batch of synthetic marijuana that's put more than 150 people in the hospital.  The highs they deliver are dangerously potent, they've caused psychotic reactions, kidney failures and suicides. But law enforcement is having a tough time keeping ahead of the chemistry involved. Investigative correspondent Drew Griffin recently went along on a major raid.