Much like the Big Surprise that awaits the viewer on this week’s other opener, Angel Eyes, the surprise ending of Shrek isn’t apt to startle anyone over the age of 10. There, however, all similarity between the two films ends, because Shrek is one of the season’s biggest and best delights. I was prepared to not much care for the film at all. I wasn’t entirely sure if I was ready to consider this completely computer-animated work a film in the first place. The idea seemed more like some aberrant homunculus of cinema. However, the point of Shrek is that it places all its strengths in the human invention of its writers and actors, while its animators have used the freedom of the computer to achieve some amazing images. It’s fresh, funny, inventive and a little subversive. (Anyone who has ever suspected that even the air at Disney World is made of plastic will appreciate Shrek’s “perfect,” sanitized theme park city, Duloc — complete with a set of rules annoyingly sung by irritatingly cute, obnoxiously perky animatronic “It’s a Small World” knock-offs.) There has been a tendency for cartoon features to be more and more smart and savvy in recent years — a kind of outgrowth of the “Fractured Fairy Tales” from Rocky and Bullwinkle — but Shrek takes this approach to new heights. An unimaginable host of savvy referential gags are housed in the standard fairy tale about an ogre, Shrek (Mike Myers doing a Scots dialect), and his side-kick, Donkey (Eddie Murphy at his most appealing), rescuing Princess Fiona (Cameron Diaz) from a castle guarded by a fire-breathing dragon. The switch of having Shrek rescue the Princess not for himself, but for the cowardly, nasty and vertically challenged Lord Farquaad (John Lithgow), only to fall in love with her himself isn’t unique (Tristan and Isolde, anyone?). What is unique is that Shrek is essentially a hired-gun doing this in order to get Farquaad to rid his swamp of all the fairy tale creatures the despotic ruler has banished there. (Farquaad feels these “misfits” ruin his otherwise “perfect” kingdom.) The true delight of the film, though, lies in the endless procession of genuinely funny riffs on fairy tales and nursery rhymes, as well as modern-day myths (the film contains references to everything from Babe to Dungeons and Dragons). In one of the film’s most outrageous scenes, Farquaad tortures the Ginger Bread Man (who blurts out, “Eat me!” and spits icing in the ruler’s eye) for information on refugee fairy-tale characters; the dialogue between them effortlessly slides into an intensely dramatic recitation of “The Muffin Man.” It’s charming, yet sounds for all the world like something out of a Woody Allen picture. The Magic Mirror reveals three choices of possible princesses for Farquaad in the manner of The Dating Game (“Although she lives with seven men, she’s not easy,” it announces of Snow White). This isn’t to indicate that the film is nothing more than a series of great gags. Shrek very much has a heart and a message (being what you are matters, trying to fit in doesn’t). The lovingly antagonistic relationship between Shrek and Donkey is beautifully developed without ever toppling into saccharine sentiment. And the gradual awakening of feelings between Shrek and Fiona is equally well-achieved. But the greatness of the film lies in its ability to put a new spin on animated film cliche. It may follow the cartoon pattern of being a musical, but the songs are not what you expect — either used satirically (“That was irritating!” remarks Shrek after Robin Hood has a rather, well, irritating production number) or as rethinkings of established pop tunes (“I’m a Believer”). In many ways, Shrek may be more a reshuffling of existing elements than anything strictly original, but what a glorious reshuffling it is!