Willard

• Husband-and-wife animal trainers Moe and Nora Di Sesso trained the film's rats — not Hollywood trainer Frank Inn, who had no involvement in Willard. They started with a dozen pet-store rats and spent about a year breeding and training roughly 500 of their offspring for the production.
• For the film's climactic scene, the crew smeared Bruce Davison with peanut butter and dumped around 600 rats on him inside a chicken-wire enclosure. Davison later said the rats "just went for the peanut butter and didn't bite me once" — no tetanus shots required.
• Composer Alex North (Spartacus, A Streetcar Named Desire) scored the film with a deliberately whimsical, almost cheerful theme that curdles into dissonance as Willard's control over the rats collapses, rather than leaning on conventional horror stings.
• The story is adapted from Stephen Gilbert's 1968 novel Ratman's Notebooks. The film was a genuine box-office hit — the 11th highest-grossing release of 1971 — and spawned a 1972 sequel, Ben, plus a 2003 remake starring Crispin Glover as Willard, with Davison making a cameo as Willard's father.

The rats function not as external monsters but as a physical manifestation of Willard's id, acting out the violent impulses his repressed psyche cannot acknowledge until it is too late.

Ben the rat represents a surrogate father figure replacing Willard's late biological father, creating an Oedipal triangle where Willard must destroy the surrogate father to claim independence, only to fail.

Willard Stiles is a browbeaten office drone, humiliated daily by the boss who stole his late father's company and nagged at home by a suffocating mother. His only comfort is the rat colony nesting in his crumbling family estate. Bonding first with a gentle white rat he names Socrates and then with a cunning, dominant black rat named Ben, Willard trains the growing colony to obey his commands — and turns them loose on the people who've wronged him. The squeaking horde becomes an extension of his repressed rage, but controlling a feral army demands a sacrifice of sanity. When Willard finally tries to cut Ben loose, the line between man and rodent blurs completely, and he learns the hard way that even his most loyal subject can turn on its king.