Glamorous, beautiful and apparently independently wealthy Melanie Daniels has one of those “cute meets” more common to romantic comedies than suspense thrillers while she stops into a pet shop in San Francisco. The other side of this romantic equation is Mitch Brenner. Mitch is an up and coming lawyer who is in the pet shop for the purpose of buying a pair of lovebirds to take home to his little sister Cathy. Cathy is truly a little sister: she’s still a child and much, much younger than Mitch.
Revealing a significant character trait of acting on impulse without regard to immediate, short-term or long-term consequences that seems to be a common strain among those with money, Melanie opts to purchase the pair of lovebirds on her own dime and take them to the Brenner home on the island situated across Bodega Bay. On the way back to the mainland alone in a small motorized boat, a seagull suddenly lunges toward Melanie’s head, leaving a bloody gash behind before soaring off to safety.
Mitch is waiting for her on the pier and decides to invite her back to his home after examining her injury. The next day when his sister Cathy is attending a birthday party, the children are attacked by a group of birds. By nightfall, hundreds of small birds appear to have intentionally made their way down the chimney inside the Brenner home for the seeming purpose of terrorizing the human inhabitants.
By now, it has become clear that the entire town seems to be under some sort of attack by birds, although a local ornithologist argues strongly against reading any intent into the attack. Nevertheless, the terror only seems to be ramping up as a series of attacks prove increasingly more violent and distressingly more directed. An attack by the birds directly leads to the death of a local farmer who is discovered by Mitch’s mom with birds pecking out his eyes. When Melanie heads to Cathy’s school out of concern over the growing danger, the realization that a murder of crows has gathered on the jungle gym behind her almost as if in a strategic deployment leads her to warn the teacher and her students who are thereupon set upon by the black birds as they try to outrun the onslaught. The birds also indirectly cause a conflagration at the local gas station which leads to what might best be described as a swarming bee-like assault upon the town with the epicenter being the diner where Melanie and the ornithologist have witnessed the incidents leading to the gas explosion.
Melanie seeks refuge in a phone booth and is rescued by Mitch. When they finally make their way back to the diner, Melanie is accused by some of the townsfolk of somehow being responsible for the attacks since they coincided with her arrival on the island. Mitch returns Melanie to Annie—the schoolteacher’s home—where she was staying, only to find that the birds have killed her. They then make their way home to the Brenner house.
Attempts are made to keep the birds at bay with Mitch boarding up all areas of entry. Outside, an endless torrent of birds attack the house. By the middle of the night, the sound of the birds attacking the home seems to subside, but during this lull—while the others sleep—Melanie hears fluttering above her. She makes her way to the attic and gets trapped inside, the victim of a viciously violent assault by birds. Mitch is finally able to rescue her, but she seems to be inching closer to madness after being at the center of four different bird attacks. Mitch decides it is time to time try to make it to their car in order to get to San Francisco and—hopefully—safety.
As the Brenners’ and Melanie exit the door, the birds almost eerily stand by watching them without attacking, allowing them to make it to the car safely. As they slowly drive away, thousands or perhaps even millions of birds sit perched and watching as if secure in the knowledge that their reign of terror has come to an end because they have to regain their natural position of dominion over their domain.