Secret Message In McDonalds Advert is a video posted to YouTube in August 2010. It was uploaded by user brainbash1.
The video starts with text that talks about a strange discovery in the McDonalds logo. The logo is displayed for a split second afterwards. More text asks if you've seen it. It then proceeds to show it again, but after the second flash, a monstrous clown appears with two rather loud screams.
NOTE: This video contains a Screamer