Heaven help us all.

Has Clint Eastwood, the macho man known for hanging desperados high and blowing up moods with moody downers like “Mystic River,” turned into an old softy?

Kind of.

In “Hereafter,” his soulful exploration of the great beyond, Eastwood drops the tough guy facade and deals with his most heartfelt subject yet — our demise.

None of us should be shocked by the veteran filmmaker’s tonal shift. His last film, “Invictus,” a rah-rah crowd-pleaser about Nelson Mandela unifying a divided South Africa through rugby, sent out an inspirational message that a change was brewing.

But no matter how exciting it is to watch a master director dive headfirst into existential matters that are thoroughly ignored by Hollywood, there’s no denying in “Hereafter” that he’s foiled by a screenplay that sputters out during a sappy final act. The ending is a tangle of contrivances that ring false.

That doesn’t mean the three story narratives driving the movie are ineptly written and unworthy of your time.

Rip away the unfinished wrap job by screenwriter Peter Morgan (“The Queen” and “Frost/Nixon”) and you will behold a cinematic keepsake with a few cracks in it.

At least the first two-thirds of “Hereafter” works very well; parts are profound.

Morgan sets up the story well, in classic triptych mode with a trio of characters — a French TV journalist, a San Francisco psychic and a London kid — grappling with death and the afterlife.

The film opens in spectacular fashion with reporter Marie Lelay (Cecile de France) getting brutally swept away by a tsunami in Indonesia. It’s a special-effects jaw-dropper, staged grippingly by Eastwood.

Battered and drowning, Marie stumbles up to death’s fuzzy doorstep, then departs from it. Her brush with mortality haunts and then changes everything in her life: a successful career, a steamy romance with her producer and a tony book deal. It also catapults the hard-hitting journalist into a humbling metaphysical investigation.

The most heart-wrenching, and satisfying, story belongs to Marcus (played by twins George and Frankie McLaren). After an accident kills his twin brother, a despondent Marcus further sinks into despair when separated from his druggie mom. Abandoned and incomplete, Marcus is becoming his own specter while grieving for his dead brother.

The least successful character turns out to be George (Matt Damon), a Bay Area psychic who sees his “gift” of talking to the dead as a curse. Lonely, he takes the occasional client when prodded by his brother (Jay Mohr). George works at a factory and takes a night cooking class in San Francisco, where he encounters another looking-for-love lost soul (Bryce Dallas Howard). Their romance dies when he does a reading of her.

In impressive fashion, Eastwood makes each scenario atmospherically different, framing George in shadows, adding a grainier texture to the film stock during Marcus’ tale and tenderizing Marie’s journey with a lighter look.

The director draws out convincing performances from de France and the McLarens, boys guaranteed to make you sob. Less successful is Damon, who goes for a listless and solemn George.

We appreciate what Damon is doing, but his bland approach is at odds with the emotional breadth of “Hereafter,” an emotional plumbing of intimate questions about death and dying. “Hereafter” never realizes its lofty ambitions, and winds up delivering wise but well-worn advice heard before — enjoy life, learn to love, let go of the past.

That’s a bit of a letdown considering what has preceded it. But maybe, just maybe, those pat slogans carry even more weight in the hereafter. Guess we’ll just have to get to the other side to really find out.