Above: Dr. Sanjay Gupta leads Q&A following a screening in New York City of Weed: Sanjay Gupta Reports with Paige Figi, who is featured in the film with her family.)

Last night, CNN held a private screening of its documentary, Weed: Sanjay Gupta Reports, for employees and special guests at Time Warner's New York headquarters. In the one-hour program, which premieres Sunday at 8 p.m. ET, CNN's chief medical correspondent, Dr. Sanjay Gupta, explores the controversial debate on the legalization of marijuana and the potential benefits for people who use it for medicinal purposes.

Over the course of a year, Dr. Gupta traveled the globe, speaking with doctors and researchers to uncover the latest findings from cutting-edge research on the study of marijuana.

He also met with the family of five-year-old Charlotte Figi, who suffers from a rare condition called Dravet's syndrome, making her prone to up to 300 seizures per week. In her home state of Colorado - where the increasing popularity of marijuana has resulted in its legalization for recreational and medicinal use - Gupta followed Charlotte's parents as they tried numerous treatments to help their daughter before considering medicinal marijuana as a last resort.

Watch a preview below to learn more and don't forget to tune in to CNN this Sunday, August 11, at 8 p.m. ET, for the premiere of Weed: Sanjay Gupta Reports.

Photo Credit: Larry Busacca/Getty Images for Time Warner