The great white shark is supposed to be the ultimate predator in the sea, but scientists may soon have to face an even bigger fish.

According to News.com.au, a team of Australian researchers is investigating the abrupt disappearance of an especially large great white, a nine-foot specimen they were tracking with a GPS device. Data from the device, which suddenly washed ashore, suggests a larger creature, a "mysterious sea monster," ate the shark.

The researchers said the tracking device showed a rapid rise in the shark's temperature, most likely from entering another beast's digestive system. There was also an indication of a swift drop of 1,900 feet (580 meters). It is currently the only theory the team has, but they believe a "colossal cannibal great white shark" ate their especially large specimen.

The Smithsonian Institute will air its own documentary on the mysterious sea predator on June 25. "Hunt for the Super Predator" follows filmmaker David Riggs' search for the massive beast that devoured Alpha, the shark the researchers were tracking.

NBC News reported Riggs has developed an obsession (similar to Captain Ahab) to find this "super predator" 11 years ago. The Australian Southern Ocean and the giant squid, killer whales and great white sharks that live in it have fascinated the filmmaker.

"The mission to uncover what took out our shark has overtaken my life," Riggs says in the documentary. "It's almost like a drug."

But R. Dean Grubbs, a shark researcher at the Florida State University Coastal and Marine Laboratory, said he does not think this case is anything too special.

"I don't know this story... but it doesn't take some mysterious giant shark to eat a 9-foot white shark," he told NBC News. "Two 10- to 12-foot sixgill sharks were eaten by what we believe, based on the vertical tracks, were larger tiger sharks... And one 10-foot tiger shark was eaten by what we are pretty certain was a larger sixgill shark. I have also caught multiple sharks that would have been over 10 feet, but only the head remained."

With the Discovery Channel's Shark Week 2014 approaching in about two months, Carlos Duarte, director of the University of Western Australia's Oceans Institute, said Riggs' documentary may just be a way to capitalize on what TV viewers want to see.

"Honestly, the thrill of society and TV stations for evil marine monsters is not really contributing much to public understanding of the oceans, but they do still serve the role of scaring the public if this is the intent," Duarte told NBC News. "Any car on the street is far deadlier than the most evil marine predator."