Rehana Sultan was all set to be a path-breaker. The time was right. Hindi cinema had emerged from the 1960s musicals era. But somehow, leading film-makers of the time did not believe Rehana had that cachet. It was Zeenat Aman who ended up being the definitive taboo-trasher of the era. Dinesh Raheja salutes the trendsetter of the 1970s, Rehana Sultan.