Rendering Movieclip Behind All Objects?

Hey All
i have a set of thumbnails which loads videos from a xml file
but the problem is that when i click on thumbs the video seems to get loaded in front of everything. The swf shows correctly but local dosent’…
and the funny thing is that wen i resize the movie in html ,movie loads in front hiding the thumbs.
How can i render movieclip behind all objects?