Alfred Hitchcock's iconic 1963 film The Birds is remembered for its high concept and cutting-edge special effects of the time. Considered by Hitchcock to be potentially "the most terrifying motion picture" he had ever made, it centered around a small town attacked by its local avian population. It was based on a short story by Daphne du Maurier. Hitchcock adapted another of the acclaimed author's stories, Rebecca, in 1940 to great success. And even though she would not be as pleased with his second endeavor, it would still go on to become one of his most well-known movies.

The Birds was nominated for an Academy Award for Best Special Effects at the 36th Oscars ceremony. Hitchcock would go on to receive the Bengal Film Journalists' Association Director Award. But it was the former accolade that created an unexpected and unique tie for the King of Horror -- a filmmaking collaboration with one of The Walt Disney Company's most legendary talents.

Ub Iwerks is best known as an animator who worked with Walt Disney in the earliest days of his fledgling studio. Neal Gabler's biography of Walt, Walt Disney: The Triumph of the American Imagination, outlined the close collaboration the two artists had for years. They met in 1919, working in a Kansas City art studio and eventually transitioned into animation together. Iwerks' signature style was present in the earliest Disney cartoons such as Oswald the Lucky Rabbit -- eventually stolen from Walt by Universal -- and subsequently Mickey Mouse. He singlehandedly animated the first Mickey Mouse short audiences saw, "Plane Crazy." This was also the case with shorts such as "Steamboat Willie," "The Skeleton Dance," and "The Haunted House." But, as related by Gabler, the relationship between Walt and Iwerks soured over time.

In January 1930, Iwerks severed his ties with The Walt Disney Company. The story was that at a Hollywood party, Walt was asked to draw a picture of Mickey Mouse and proposed that Iwerks draw the picture, and he would sign it. Iweks felt undervalued and left Walt's side to start his own company. Only, he was not nearly as successful at running a studio as he was as an animator. In 1940, 10 years after his fallout with Walt, he would return to Walt Disney Studios in a different capacity. This time, he lent his talent to the development of special visual technologies and effects -- something he had always had a knack for.

During his time working in special effects at Disney, Iwerks was credited with a number of advancements in the industry. As early as Walt's Alice Comedies, Iwerks developed the technology for combining animation and live-action, which would later be used in movies like The Song of the South (1946) and Who Framed Roger Rabbit (1988). He also assisted in the creation of a "process that allowed animator's artwork as in 101 Dalmatians (1961) to be transferred directly to xerox cels and thus eliminated the costly and time-consuming inking process." His hand could be seen in 20,000 Leagues Under the Sea (1954) in the artwork for a coral reef as well. The Disney Parks can thank Iwerks for his contributions to attractions such as It's a Small World, Pirates of the Caribbean, and Haunted Mansion. Before his death from a heart attack at 70, The Hall of Presidents at Walt Disney World would be the final attraction Iwerks would work on.

For Hitchcock's The Birds, Iwerks would log more than 300 hours on special effects projects. Hitchcock reached out to Iwerks himself to ask if he would be interested in working on the film. The seasoned animator would spend weeks working with an optical printer to figure out the effects of the sparrows flying down a chimney en masse. He would also engineer a type of sodium vapor process photography for the group of tiny birds flying around the glass phone booth with film star Tippi Hedren inside. Iwerks was credited as Special Photographic Advisor on the film and the movie would receive an Oscar nomination, but ultimately lost out to Cleopatra. Iwerks worked with an entire team of special effects artists on The Birds, but his contributions were invaluable.

The Birds was not an original concept, but an adaptation of du Maurier's short story "The Birds" published in 1952. The story takes place in du Maurier's homeland of Cornwall, England, following World War II. A disabled war veteran named Nat Hocken works on a farm along the coast and notices odd behavior in the local bird population. His family are attacked by birds in their home shortly thereafter. Similar attacks begin to pop up all over the United Kingdom and a national emergency is declared shortly thereafter. As Nat and his family shelter in place, he makes the connection that the birds' behavior is tied to the sea tides -- the story ends with him hunkering down with his family as the birds continue to attack their home, and he watches the fire burn in their fireplace.

In order to make the story work for a film, major changes were made to the source material. Screenwriter Evan Hunter would develop new characters with Hitchcock and a more elaborate plot. In his book, Me and Hitch, Evans talked about how they borrowed elements from the screwball comedy genre to build out the beginning of the film so the change to horror mid-film would feel jarring. Audiences would know from the previews what was coming, but they would not know when. The story would also be reset from a Cornish coastal town to the Northern California Coast. An interesting choice considering Hitchcock was a Brit himself.

The shift of location was something du Maurier especially disliked about the film. Critics have pointed out how the alteration removes a core tenant of the story's tone and atmosphere. How "the combination of bleak landscape and rustic characters [of Cornwall] lends an appropriately elemental tone to the tale, and this is missing from Hitchcock's version, with its placid northern California setting and the urbane city folk he casts as his protagonists." As often goes with text to screen adaptations, the story went "Hollywood." Although the movie does have an ending somewhat as open as the original story -- the main characters drive away from town into an uncertain future as the birds watch. Despite her disapproval, du Maurier could not keep the movie from becoming a cultural icon for the genre.

In 2016, The Birds was inducted into the National Film Registry for its cultural, historical, and aesthetic significance. But a consensus of approval was not the initial reaction to the film from critics. A well-known critic at the time, Bosley Crowther, was not sure what to make of it. He was confused whether there was meant to be a lesson in it all, stating:

. . . it isn't in Mr. Hitchcock's style to inject allegorical meanings or social significance in his films. But the context of the birds concentrating their fury upon a house in which a possessive and jealous mother hovers anxiously over her son is so obvious and fascinating that I rather lean to it.

Stanley Kaufmann recorded in his 1966 book, A World on Film, that his initial reaction was that The Birds was "the worst thriller of [Hitchcock's] that I can remember." Bendan Gill of The New Yorker called it, "a sorry failure" that "transforms the sadism that lies at the heart of every thriller . . . all too nakedly, repellently present." Still this did not stop international filmmakers like Akira Kurosawa from including it in his Top 100 Favorite Films of All Time.

The respect for Hitchcock's work has seemed to only expand and grow over time. Even if more unpleasant sides of his character on a personal level have emerged -- such as his treatment of Hedren during production -- his movies tend to remain in a league of their own. In the end, perhaps, the credit should actually go to du Maurier, who inspired it all to begin with. And Iwerks for his incredible technical contributions to cinema.