Randomise internal images, non-external and dynamically loaded

Rather than external images.

If I have three images within my movie is there a way of randomly displaying an image from the two images available?

This does not really need to be dynamic as I think only three images will be in use, and if they want them changing I can do this.

So lets say I have three images within my movie, as symbols. I am assuming you would use attachMovie, and also assign a linkage value of maybe 1,2,3 but what else would be required to randomize internal images.

Because what I want to do is preload them all as one set in the first instance, and then in other pages I will no longer need a prelaoder as the images would have already loaded into cache.

Any help would be great.

Trev