Dr. Emma Collins and her team are spending their third summer on the island of Little Happy studying the effect of climate change on the great white sharks who come to the nearby nursery every year to give birth. Along with the last two inhabitants of this former fishing village, their peaceful life is disrupted when a "scientific" team led by her ex-boyfriend and marine biologist Richard show up looking for three bull sharks who we soon learn aren't just any bull sharks.
U.S. Navy SEAL Chris Kyle (Bradley Cooper) takes his sole mission—protect his comrades—to heart and becomes one of the most lethal snipers in American history. His pinpoint accuracy not only saves countless lives but also makes him a prime target of insurgents. Despite grave danger and his struggle to be a good husband and father to his family back in the States, Kyle serves four tours of duty in Iraq. However, when he finally returns home, he finds that he cannot leave the war behind.