Bearing almost no resemblance to the original Anaconda, Anacondas: The Hunt for the Blood Orchid is more a throwback to B-movies of the late 1950s. As a special-effects extravaganza, it's pretty tepid stuff, but as a jungle potboiler, the movie has just enough campy thrills to keep customers satisfied.

Entrepreneur Gordon Mitchell (Morris Chestnut) and his scientist-partner Jack Byron (Matthew Marsden) learn about a rare jungle orchid that could prolong life, a discovery 'bigger than Viagra.' But they only have a few weeks before the elusive flowers disappear for years. Accompanied by Gail (Salli Richardson-Whitfield), a venture capitalist, they head off for Borneo in search of the blood orchid.

Others on the team include Sam (KaDee Strickland), a beautiful scientist and the object of Byron's attentions; Cole (Eugene Byrd), a computer expert and the film's primary comic relief; and Ben (Nicholas Gonzalez), a doctor whose cast billing provides all you need to know about his fate.

Since it is the rainy season, the only captain reckless enough to take them upriver is Bill Johnson (Johnny Messner). Trouble arrives almost at once. Armed only with a knife, Johnson fights off a hungry crocodile, then loses his boat over a rain-swollen waterfall. He must lead the others through the jungle in search of help.

A hike through a swamp to a deserted native village confirms Johnson's fears: The area is infested with giant anacondas. Byron insists on continuing the expedition, stopping at nothing to find the orchids. The survivors must figure out a way to escape the anacondas.

For much of the movie, director Dwight Little holds off on snake attacks, relying on diversions like venomous spiders to provide shocks. (It's just as well, since the primitive effects used for the snakes inspire more laughs than fear.) For long stretches, Anacondas resembles a stripped-down episode of "Survivor,' with a bit of "Fear Factor" thrown in. Perhaps as a result, the multi-ethnic cast is reduced to a cross-section of annoying yuppie types. Messner seems intent on channeling Hugh Jackman, while Strickland too often looks befuddled. Only bug-eyed Byrd and contemptuous career girl Richardson-Whitfield find much meat in their roles.

Still, everyone seems to have enjoyed the Fiji locations (standing in for Borneo). The film's principal tone is one of good-natured joshing, and the overall lack of cynicism and cheap tricks is refreshing. The bigger issue is whether teen audiences used to much more violent, bloodier fare will find Anacondas at all interesting.

-Daniel Eagan