Chicken Run” has arrived to the joy and relief of the many fans of Nick Parks’ Oscar-winning Wallace and Gromit short films. In his studio’s first feature-length movie, a brave chicken plots an escape from a small Yorkshire chicken farm.

The stern and angry Mrs. Tweedy (voice of Miranda Richardson) and her brow-beaten (should we say hen-pecked?) husband have bullied their hens into producing eggs, but now they have set up a fierce-looking machine that turns chickens into chicken pies. Ginger (voice of Julia Sawalha) is a smart, brave, loyal chicken who will not leave unless she can take the others with her. When an American circus rooster named Rocky (voice of Mel Gibson) arrives, Ginger gets him to agree to teach the chickens to fly over the fence, so they can find a place where they can live in freedom.

Parks is a master at creating a world that is enchantingly believable. The farm seems to be set in the 1950’s, and every detail, down to the last nail in the last board on the hen house wall, looks exactly as it should. Though his painstaking process produces only a few seconds of film footage each day, every frame is filled with vivid personalities who seem to be moving in real time, each creating an instantly recognizable character. One look at Mrs. Tweedy’s formidable Wellington boots marching into the hen yard for inspection, and we know everything about her. The chickens are highly individual, completely believable, and wildly funny, whether doing Tae-Bo-like exercises for increasing wing power or a celebratory Lindy hop. But I admit that my favorite characters are two forager/thief rats who are so completely charming that it is impossible to imagine anyone objecting to their stealing.

The movie also features Parks’ special talents for creating deliciously malevolent machines and split-second action sequences. Ginger and Rocky fall into the chicken pie machine for a scene that combines Rube Goldberg complexity of gears and operations with the breath-catching near misses of Indiana Jones.

Three cheers for producer Dreamworks, who let Parks be Parks and didn’t focus-group him into making something more linear and accessible. What that means, though, is that the movie does not have some of what both adults and kids expect in a G-rated movie. This is not a musical in which the heroine sits down 15 minutes into the story to sing about her dreams or adorable sidekicks provide comic relief.

This is not a script with jokes that children will necessarily understand. Indeed, given that most of the parents of today’s school-age children were born 20 years after the 1950’s, there are several jokes parents may not understand, like a pointed reference to the delay in the US entry into World War II and a couple of witty tributes to the classic movie, “The Great Escape.” The movie has a decidedly British point of view, with a wonderful range of accents that will be much more meaningful (and understandable) to English children than they are to Americans. Parks is like Bugs Bunny creator Chuck Jones, who, when asked whether he made cartoons for adults or children, replied, “I make them for myself and my friends.” But, as with Bugs Bunny, kids will enjoy the world created by this movie, and will rejoice in the chickens’ adventures.

Parents should know that although the movie is rated G, it may be too scary or hard to follow for children under 6 or 7. A minor character is killed off-screen and characters are in peril throughout the movie.

Families who see this movie should talk about why it was hard for Rocky to tell the truth, and even to understand what telling the truth meant, as when he said, “I didn’t lie to them, dollface. I just omitted certain truths,” and when he tells Ginger that if they want the chickens to perform they have to tell them what they want to hear. Talk, too, about Ginger’s perseverance in the face of “million to one” odds, and her refusal to escape without her friends, and about the importance of leadership and teamwork. Ask kids why Ginger had a dream of freedom that some of the other chickens could not even imagine, and what it meant to say that “the fences aren’t just around the farm – they’re up here on your head.”

Families who enjoy this movie will also enjoy Parks’ Wallace and Gromit videos: “The Wrong Trousers,” “A Grand Day Out,” and “A Close Shave.