Play video content

We know it sounds ridiculous ... but the Internet is buzzing with rumors that Beyonce is NOT really pregnant and she's wearing a fake stomach in an elaborate cover-up. Now, a controversial new video is fueling the fire.

Beyonce appeared on an Australian TV show this weekend called "Sunday Night" -- wearing a tight red dress that accentuated her baby bump.

But when B sits down in her chair, her bump appears to collapse inward, leading many to believe it's not B's real bump after all ... but a prosthetic device intended to deceive.

So why would B fake preggo? There are rumors that she has hired a surrogate mother to carry the kid, so she won't have to put her body through the strains of pregnancy.

But color us skeptical -- because last month, Bey bared all during a vacation in Croatia with Jay-Z ... revealing what looks like a totally legit baby bump.

We called B's camp for comment -- but we haven't heard back yet.