BENJI THE HUNTED - Washed into the sea while filming a movie scene, the indestructible pooch swims ashore and has an adventure with a hunter and a bunch of orphaned cubs. There are few surprises in the story, but it's fun to watch filmmaker Joe Camp tell his tale almost completely through images, with little dialogue or narration. (Rated G) MILLION DOLLAR MYSTERY - Slapstick yarn about greedy treasure hunters and a stashed-away fortune. A real-life contest is tied into the movie: Clues are buried in the story, and the audience is invited to guess, by mail, the location of the loot that's still missing at the end. The film is as entertaining as you'd expect, considering how much the producers are offering us to pay attention. Directed by Richard Fleischer. (Rated PG) MOONFLEET - Revival of Fritz Lang's colorful 18th-century saga about a spunky lad, a rogue who takes him in, and a treasure. First released in 1954 by MGM. (Not rated) PREDATOR - Arnold Schwarzenegger fights an outer-space monster in a third-world jungle. The monster never has a chance. Neither does the jungle. Neither does the audience. Directed by John McTiernan, who serves up the violence with bone-crunching gusto. (Rated R) SUMMER NIGHT: WITH GREEK PROFILE, ALMOND EYES & SCENT OF BASIL - Lina Wertm"uller returns frequently to metaphors of imprisonment in her fierce socio-political comedies, which attack the arrogance of extremism on both right and left. This time a female capitalist kidnaps a male terrorist, only to fall in love with his absurdly macho personality. Technically, the Italian filmmaker hasn't been in such good form for years. But this follow-up to the overrated ``Swept Away ...'' is marred by its own excesses of overcooked language and imagery, and by Wertm"uller's tendency to see all behavior in terms of sexuality. (Not rated) THE WITCHES OF EASTWICK - They're suburban women with half-baked magical powers, and all three fall for the new man in town, an oversexed lout who's clearly a devil in disguise. Although it's based on a provocative John Updike novel, which uses casual witchcraft as a symbol for contemporary ills, the movie is more interested in gross-out effects inspired by ``The Exorcist'' and other childish entertainments. The result is stupid and vulgar, with only a few breaks in the clouds, including an enchanting tennis-match scene. Directed by George Miller, who tosses in a car-chase episode to remind us that he directed the overpraised ``Mad Max'' movies. (Rated R) WITHNAIL AND I - In the dying days of the psychedelic '60s, two burned-out and boozed-up actors head for a bleak summer vacation in the country. The atmosphere of the period is captured with grim hilarity, and the performers effectively blend overtones of hysteria with undertones of despair. The mood turns monotonous after a while, though, and the plot dwells endlessly on a homosexual-baiting subplot. Written and directed by Bruce Robinson. (Rated R) RATINGS: Films with ratings other than G may contain varying degrees of vulgar language, nudity, sex, and violence.