DAKOTA JOHNSON has a box-office smash with the kinky hit film “Fifty Shades of Grey” – but friends fear the daughter of Melanie Griffith and “Miami Vice” star Don Johnson is risking a return to rehab! 

The 25-year-old starlet has a troubled secret past, including a stint in a 30-day treatment program for drug and alcohol addiction when she was just 17, The National ENQUIRER has learned.

Said a family insider: “Dakota was out of control at the time, and if she didn’t get help, she may have very well ended up dead or in jail.”

Now close pals are worried about Dakota handling the pressure of newfound fame – especially since her parents have an extensive history of destructive addictions!

Don was admitted to the Betty Ford Center in 1994 for drug and alcohol abuse, and returned to rehab in 2001.

Melanie became a star with her own daring role as a porn star in the 1984 thriller “Body Double,” and has spent at least three stints in rehab, struggling with painkillers, alcohol and cocaine – most recently in 2009.