Playing a movie backwards

I’m working on a flash movie. It is of some testimonials that the user clicks next or previous to transition through them. When pressing next its fine since the text fades out as the next text fades in. But i want to replicate this for clicking previous, ie, instead of the button jumping to the set frame, i want it to play the few frames backwards to the faded in state. Does this make sense?? I’d really appreciate the help on this.