More than six years since CNNs first investigation into medical marijuana, Dr. Sanjay Gupta searches for the truth about CBD, which has turned into a multi-billion-dollar industry.

Fareed Zakaria looks at the frenzied competition for slots at elite schools that has exploded into the biggest cheating scandal in American history, a scheme that exploited the desperate quest for higher test scores.

In the last few decades, impeachment has become a political weapon. Now we find ourselves in the middle of an impeachment inquiry, looking to history to understand how, why, and even if Donald Trump should be impeached.