Robert Downey, Jr. almost defines the celebrity rehab revolving door -- he was introduced to drugs when he was only 8 years old (reportedly by his father, among others -- yay, parenting!), and entered rehab for the first time in 1987 when he was 22 years old. In 1996, he was arrested multiple times on drug and weapons charges, and spent the next four years cycling through rehab and prison -- and drugs such as heroin, cocaine and crack. He finally seemed to emerge from the grip of addiction in 2001. Of course, he then went on to play famously alcoholic Tony Stark in the Iron Man movies -- and we're hoping we'll one day see him take on the famous "Demon in a Bottle" storyline from the comics.
- Sarah Jersild, The CW Source