“Bluefin” is a captivating story set in North Lake, Prince Edward Island, known as the “tuna capital of the world.” Filmmaker John Hopkins embarks on a quest to unravel a perplexing enigma: the typically cautious bluefin tuna have become unafraid of humans, and the reason remains elusive. Local fishermen and scientists are left bewildered, providing differing theories to explain the tuna’s unusual behavior. What is undeniable, however, is that the remarkable return of these massive fish contradicts scientific reports indicating that their endangered populations have dwindled by 90 percent.