After months of waiting and wondering, last night I finally got to see the movie version of “Sweeney Todd.” I’d seen the stage production years ago, with Angela Lansbury and George Hearn, and knew to expect something different with Johnny Depp wielding the razor. It is different. Very different. It’s a brooding, disturbing, urgent, ominous, grisly, sweeping “Sweeney.”

And it’s also something I never expected: heartbreaking.

It’s a story of revenge, and like all of these kinds of tales, the moral is the same: revenge begets revenge. (Or, as “Othello” puts it, “Sin will pluck on sin.”) The grudges we nurse can destroy us — even more so, when we believe that settling those grudges will, in fact, redeem us. When Sweeney throws back his head and sings, “I will have salvation,” he’s not talking about going to heaven, but to hell. And hell consumes, almost literally, the second half of the story, with bodies being burned and chimneys belching black smoke and corpses piling up like the last scene of “Hamlet.”

But underneath it all beats the dark and troubled heart of a good man who was transformed into a monster, and nobody does that sort of role better than Johnny Depp. He sings capably, murders viciously, and grieves bitterly. And Tim Burton and screenwriter John Logan capture small but telling details that give the story pangs of real feeling: Sweeney’s discovery of a child’s battered and decaying doll speaks volumes.

The movie is graphic, and the story is macabre — murder and cannibalism set to music? — and it won’t be to everybody’s, um, taste. (I was flabbergasted to see a lot of people last night bringing young children, 10 and under, to the movie. What may be more troubling: I didn’t hear any of them scream or cry when gallons of plasma sprayed the camera.) The story shows how far the human heart can go when it ceases to love. And it shows how a zealous and single-minded quest for vengeance can lead to self-destruction.

In a tale full of ironies and paradoxes and twists, Sweeney himself is destroyed in the end not just by his own mad vision of the world, but by something simple and almost powerless: a child. Evil is conquered by innocence. The dragon is slain by a small boy with a pure heart.

I’m not sure everyone lives happily ever after — but the fact that any of the characters lives at all is a testament, I guess, to hope.

It’s not exactly Dickens. But it may well be a cautionary kind of Christmas parable for our own bleak time. Like Scrooge, Sweeney is haunted by ghosts. But rather than learning from them, he allows his ghosts to turn into obsessions — and the result leads to his own ruin.

Curious for more? Happy Catholic has another take on the movie right here. I can’t wait to read what Julie thought of it.