attachMovie?

My navigation system is comprised of 4 buttons that have the attachMovie action script applied. I am using the attachMovie to pull up movie files that are part of that swf file.

Here’s my question: Is there a way to unattach a movie? Originally I had my attachMovie set up in layers. For example: “logo” ,1)
But it seemed that the layer were never replaced.

I guess what I want to do is figure out if there is a way to unattach a movie when another navigation button has been selected that will attach a new movie.

Thanks for your help!