It looked as if writer-director David Lowery was changing the course of his career by remaking the Disney family film Pete's Dragon and then signing up to helm a live-action version of the studio's animated classic Peter Pan. Lowery's third feature as director, though, A Ghost Story, is closer in tone to his debut, 2013's critically acclaimed and commercially insignificant Ain't Them Bodies Saints.

As in that crime drama, Rooney Mara and Casey Affleck take the lead roles here, playing a couple. We open with the two of them comfortable and close at night in their little old rural home. We don't even get their names before the man is killed in a car crash just down the road. His wife or girlfriend takes a look at the dead body at the hospital morgue and walks off. Shortly thereafter, the deceased sits up, covered by a white bedsheet. The sheet remains on and two eye holes somehow form, giving the dead man the classic, easy Halloween ghost costume look.

But it's not Halloween and this isn't a costume. The man, a musician in life, is dead and no one can see him as he walks and stands about. He heads back to his home, where his lover is distraught. In the film's most indulgent and patience-testing sequence, he watches, motionlessly from a distance, as she devours most of a homemade pie her realtor has dropped off for her.

In this stretch, A Ghost Story strikes you as a frank, understated portrait of grief. But the film takes on many different forms, all of them creative and thought-provoking in their own way. Our sheeted ghost exchanges "words" with a ghost in another house, subtitles translating their gestures. He disrupts a Spanish-speaking family that occupies the home after his widow vacates it in a sequence that kind of plays like a Paranormal Activity movie from the other perspective. Initially, the ghost can't do much more than make lightbulbs flicker and burn brighter, but he discovers he's capable of more.

But if you think this is going to turn into a horror movie from another point of view, you're mistaken. There's really no guessing where Lowery will take you on this strange, challenging journey. Nonetheless, cineastes should find it a delightful ride, with the beautiful, rounded Academy Ratio 1.37:1 visuals and compelling score engaging the senses as the unconventional story provokes your mind.

At some point, the ghost unlocks the power to travel through time, watching as a pioneer family plans to settle in the spot where he lived. This also enables us to see more of our leads' relationship when both were alive, as they get their first look at the house and he shares music with her that moves her and us alike (Dark Rooms' recurring, tone-setting "I Get Overwhelmed"). There are also signs of strain, suggesting the two were destined to split, even had death not done them part.

If you thought that Lowery's Pete's Dragon was to usher in a new age of accessible, uninspired, commercial, mainstream filmmaking, A Ghost Story defiantly proves you were mistaken. This is the kind of art film that will either not attract casual moviegoers or leave them baffled and frustrated. But there are plenty of movies made for those who don't wish to think or feel. A Ghost Story is something different and that's part of its appeal, but far from all of it.

This film is haunting and original and brave. A central sequence finds a character we never see before or again dissecting the fleeting nature of immortality, using everything from Beethoven's Ninth Symphony to the Sun's expansion into an Earth-swallowing red giant to prove his point. That scene feels like a brush with Terrence Malick's universal ponderings. In other ways, Ghost recalls an alternate version of Affleck's recent Oscar winner Manchester by the Sea or Mara's Her. It doesn't borrow from such triumphs, as much as hit upon some of the deep emotions that they did so well.

Since it's opening in July, across from Spider-Man: Homecoming and other popcorn movies, A Ghost Story seems to have little shot at sustaining its critical buzz until awards season. Then again, the distributor's similarly weird and original The Lobster opened in May and managed to score an Oscar nomination for Original Screenplay last year. After premiering at Sundance this past January, Ghost would probably be lucky to score an Independent Spirit Award nomination or two, the way that A24's similarly timed Swiss Army Man did a year ago.

Buy A Ghost Story from Amazon.com: Blu-ray + Digital HD / DVD / Instant Video