If you are predisposed to distrust big business and the bureaucrats who regulate it, then “Gasland,” a soberly muckracking film about the health and environmental dangers of the current nationwide rush to drill for natural gas, will light a flame in you...

The accumulation of stories and sympathetic faces is persuasive; it’s buttressed by testimony from scientists like Theo Colborn and Al Armendariz, named regional director of the Environmental Protection Agency in Dallas since the film was completed. Most viewers who seek out “Gasland” are likely to share Mr. Fox’s outrage (which he expresses in melancholy tones) and to accept the picture, familiar and so often true, of heedless profiteering, co-opted and ineffective regulation, Orwellian spin control and innocent, ruined lives. Comparisons to the oil spill in the Gulf of Mexico will be unavoidable...

Mr. Fox shows a general preference for vivid images — bright red Halliburton trucks, beeping but unidentified scientific instruments — over the more mundane crossing the t’s and dotting the i’s of investigative journalism...

Mr. Fox closes with an ominous warning about the threat fracking poses to New York City’s watershed. New Yorkers who are frightened at the prospect will want to know that the state recently tightened regulations governing drilling in that area, at least temporarily.