The first sign that “A Quiet Place’’ means business comes in the opening shot, in which the words “Day 89” flash on the screen. It means that the worst has happened already — with even more worst to come.

Next we see a family of five creeping through what remains of a drugstore, gathering provisions. We notice at once that they are being really, really quiet. Every time one of them almost makes noise — nearly knocks something over, comes close to tripping over something — the mother (Emily Blunt) panics.

It’s rare when someone comes up with an original angle for a horror movie. A society in collapse, alien invasion, a family struggling to survive — these are familiar and reliable tropes in sci-fi horror. What’s different here is the nature of the invaders. They hunt by sound. If anyone makes a noise, an alien shows up immediately, as if materializing out of the air, and attacks.

As a result, “A Quiet Place” is the closest thing to a silent movie since “The Artist.” From beginning to end, there is a total of maybe two pages of spoken dialogue. The family knows sign language — the teenage daughter (Millicent Simmonds) is deaf — and when they sign, the movie provides subtitles.

As the story starts, the Abbott family is migrating on foot from the city into the countryside. Then, immediately after the credits, the narrative jumps 400 days into the crisis, with the family, quiet as ever, living in the country. And one of the first things we notice is that the mother is very pregnant. Uh-oh. Babies are noisy. For that matter, childbirth is pretty noisy. What’s going to happen to these people in just a few weeks?

What follows is best left to be discovered as the movie comes to a crescendo that doesn’t stop. The second half is a series of slowly built and meticulously constructed crises, one flowing into the next, each one exceeding the other, to the point that the whole experience becomes almost unbearable — but unbearable in the best way.

Because everyone on screen is trying to be silent, the viewer becomes acutely aware of sound. John Krasinski, who directed (and who plays the father), makes use of the audience’s heightened attention throughout. At one point, an alien roars past unseen, and yet we know from the theater speaker system that it has moved, in a flash, from left to right.

Krasinski wisely throws most of the movie to Blunt, who turns out to be a strong silent film actress. She plays the mother as an interesting person whose life has become too interesting.