Demi Moore gives a career-defining performance as Elisabeth Sparkle, a former A-lister past her prime and suddenly fired from her fitness TV show by repellent studio head Harvey (Dennis Quaid). She is then drawn to the opportunity presented by a mysterious new drug: THE SUBSTANCE. All it takes is one injection and she is reborn as the gorgeous, twentysomething Sue (Margaret Qualley). The only rule? Time needs to be split: exactly one week in one body, then one week in the other. No exceptions. A perfect balance. What could go wrong?