Backwords Frames

Is there a way to make frames be read backwords?
Like if i want an animation to stop, then all of a sudden be played backwords, is there any actionscript that would allow me to do that?
Or do I have to copy and paste the frames backwords?

Thanks

on the last frame put
_root.backwards = true;
then on the other frames put
if(_root.backwards == true) {
_parent.previousFrame();
}
then on frame one put
backwards = false

should work…