image change on mouse click?

So i have this movie, there is nothing in it, its name is "1". When i load the swf there is a picture there, because the action in frame one set to:

movie = 3;
loadMovie("images/"+movie+".jpg", "1");


So it loads picture 3.jpg, which works fine. However, i have a button, and when i click it i have:

on (press) {
movie = 4;
}

So, why doesn't the picture change to picture 4.jpg? I tried it with text in a text box, and it worked pefect. This whole movie is only 1 frame, so i tried setting it to 2 frames and have it just keep cycling. How i have it set up now (whats above) works. But when it loads frame 1 the picture gets set back to 3.jpg (understandably). So i dont know what i need to do to get it to work.