A new video is rousing the interest of skeptics and people who just want to believe giant fish monsters are real. Posted by YouTuber Penn Plate, whose only other video is a time-lapse of London's skyline uploaded two days earlier, the cell phone footage shows a dark mass surfacing as it lurks through the Thames river. Watch and decide for yourself whether this is the real deal or a promotional stunt for some Cloverfield rip-off.

Sources: Penn Plate