This third film in the series follows a group of marine biologists attempting to capture a young great white shark that has wandered into Florida's Sea World Park. However, later it is discovered that the shark's 35-foot mother is also a guest at Sea World. What follows is the shark wreaking havoc on the visitors in the park.

Notorious killer whale Tilikum is responsible for the deaths of three individuals, including a top killer whale trainer. Blackfish shows the sometimes devastating consequences of keeping such intelligent and sentient creatures in captivity.