TV Show: Friends
Friends burst out of the gate in 1994 featuring three attractive actresses, but the established hottie was Courteney Cox. Aniston, who played Rachel Green, had been on the canceled Ferris Bueller TV show, but was basically a nobody.
And then, all of a sudden, there was this thing called "the Rachel" haircut. Every woman wanted their hair done like the girl on the hot show. With the haircut, the TV fame, and a true gift for comedy (trivia: she turned down a spot in the Saturday Night Live cast to take the Friends job) combined, Aniston became a big star and, before you knew it, the (former) wife of the sexiest man in the world, Brad Pitt.