Robert Downey Jr.
Popularity can really hurt you when you don’t take care of yourself. Robert Downey Jr. learned that life lesson the hard way. After the success of 1993’s Chaplin, the actor developed a drug and alcohol addiction which resulted in several arrests. Suddenly, his career went up in flames as he was written off from the Ally McBeal show. The future Marvel star spent many years working on those issues, and he clearly did well, as seen from his post-rehab projects. Not only did he land a Sherlock role, but he also became the most iconic character in the MCU – Tony Stark, aka Iron Man.