macbook pro retina and hdmi out

hey guys and gals..

wanted to watch a few flicks on my big screen off of my new MBPr.

I've hooked up the display via hdmi and went into the preferences and selected audio out of HDMI, but is there a way for me to close the lid on my MBPr and keep the link active? can't seem to figure this out.. I guess it's not a big deal leaving it open but it would be nice to just close it up while the movie is playing.

thanks!

How to operate my Mac portable computer in "clamshell mode": LINK

i would just always be cautious when doing this with hd movies. never want to risk overheating. just a point of thought