Dripping with atmosphere and heavy-breathing melodrama, “Before the Rains” certainly succeeds as a visual feast. If only it weren’t so easy to peg.

The setting is lush: India, 1937, in the green Munnar Hills. A British entrepreneur, Henry (Linus Roache), is building a road through the hills, which must be finished before the monsoon season begins.

Henry has an unusually warm relationship with his foreman, TK (Rahul Bose), a local man who is trying to straddle the cultures of the British occupiers and the Indian natives.

The problem is, Henry also has a very, very warm relationship with his housekeeper, Sajani (Nandita Das). Really warm. Let’s-go-to-the-sacred-grove-and-get-nasty warm.

Sajani has a husband, and the community has standards. Nobody wants to undergo a lie-detector test that involves putting your tongue on a red-hot spoon (although someone will undergo it before the movie is over).

Director Santosh Sivan (“The Terrorist”) seeks to tell a torrid story of love, death and cover-up, and also score some points on the issue of Britain’s colonization of India.

The maddening thing is the plot is rigged so that it depends on people doing stupid things, so it’s hard to sit back and just enjoy the lurid details. When a movie hinges on crises that could be rescued with an honest explanation, it’s in trouble.

The actors don’t have much to play with. Linus Roache (“The Wings of the Dove”) often gets cast in these weak-willed English twit roles, and he does them well. But Henry isn’t very believable.

Jennifer Ehle gets some strong stuff going as his suspicious wife, and Nandita Das (who starred in Deepa Mehta’s films “Fire” and “Earth”) is heartfelt as the unfortunate mistress. Coming off best is Indian star Rahul Bose, who really has the central role, a man whose allegiances are severely stretched between two worlds.

Sivan is a cinematographer, and he shot this film as well as directing it. It’s gorgeous to look at, but the story makes it hard to indulge.