"The Birds" is a classic movie, but if you go back and watch it in the context of Alfred Hitchcock's filmography, it's also somewhat bizarre, even by his standards.

Most of Hitchcock's best-known films are tales of murder and madness that could be classified as crime thrillers or works of psychological horror. "The Birds" is a full-on monster movie. Yet it's one that has a slow build around a series of inscrutable and not entirely relatable characters, led by Melanie Daniels (Tippi Hedren), a San Francisco socialite who's had her name in gossip columns and who's not above going to elaborate lengths to carry out a practical joke.

A chance encounter in a pet store is all it takes for Melanie to follow the lawyerly Mitch Brenner (Rod Taylor) to the fishing village of Bodega Bay, which also served as a shooting location for John Carpenter's "The Fog" and which feels like a precursor to any number of Maine-set Stephen King stories such as "The Mist." In the DVD documentary "All About the Birds," screenwriter Evan Hunter revealed that he was surprised by some of the changes Hitchcock made to his script, especially the ending. As he put it:

"I was surprised when some scenes were not in the film, but when I saw the ending I was shocked. Because, the way I had the film end, they come out of the house, and they get in the car, and they start driving away from the house. And we see them coming through town now, and we see the havoc that has been wreaked in the town, so it becomes not just a personal thing that's directed against Melanie — wherever she is the birds are attacking — we now see that this is a universal thing."

A War Against The Town

"The Birds" is a film that is not without controversy over Hitchcock's alleged mistreatment of Hedren. As gulls, sparrows, and crows begin attacking Bodega Bay, there's a scene where a hysterical mother accuses Melanie herself of being "the cause of all this," since it started happening after she arrived. The camera assumes Melanie's perspective as the woman looks right into it and shrieks, "I think you're evil!"

Later, the birds single Melanie out for a particularly brutal attack in an attic in the home of Mitch's mother, Lydia Brenner (Jessica Tandy). As Hunter explained, his ending would have made it clear that the havoc they had caused was not some "personal thing" brought on by Melanie, but rather a "universal thing." In the documentary, he further detailed how his original ending would have played out:

"We see disaster all through the town as we see an overturned school bus, we see a farmer with a shotgun lying across a front porch, we see windows shattered all over town, dead birds on the road, police patrol cars in flames. It's almost as if a war has been waged against the town by the birds. And they come to a roadblock in the road, covered with birds, and they manage to get through that. They creep along through that. And they start gradually accelerating the car and moving away and the birds all go up in the air and come at the car. And now they're going out of town on that same winding road, and the birds now are coming on a straight line for the car. And the birds descend on the car. And the convertible is also set up at the very beginning of the film, it's a convertible with a canvas top."

The Birds Take Over The World

"Now the birds land on the top of the car," Hunter continued with his description of the original "Birds" ending scene, "[…] and we see the top starting to shred, and it goes back suddenly and all the birds are hovering over the car. And we go back and we see that the road now is — the curves are ending, and [Mitch] hits the gas, the car goes ahead, and the birds fall back. You see the birds falling back, and they're in the clear. And that was the end of the movie."

Needless to say, this car chase ending, which did make it through the revision process to the shooting script, would have been much more difficult to shoot. Hunter acknowledged that it would have taken a month, requiring special effects and overhead shots from a helicopter. Production designer Robert F. Boyle said that the crew did some preparation for it, littering the road that the car would take with dead chickens and throwing ketchup against buildings to simulate blood.

Hitchcock, however — who was already known for some of his single-location thrillers like "Rope" and "Rear Window" — ultimately decided to leave the camera looking out from the house as the car drives away, while birds congregate all over the ground, fence, tree branches, and power lines. For the viewer, this final image may be enough to establish that the birds now dominate the landscape. Though Hunter envisioned "The Birds" ending with a much different chase scene, he concluded by saying, "I think maybe [Hitchcock] figured he had the same effect by showing the birds having taken over the screen, and by association the world."

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