“Ideas are like fish,” says filmmaker David Lynch. “If you want to catch little fish, you can stay in the shallow water. But if you want to catch the big fish, you’ve got to go deeper.”

I don’t know if filmmaker Paul Harrill has read Lynch’s book Catching the Big Fish: Meditation, Consciousness, and CreativityBut I thought about those lines when I watched Harrill’s new film Light From Light, which begins in a genre that often stays in the shallows but then very quickly strides into far deeper waters, its nets prepared to capture large and mysterious ideas.

More specifically, I thought of it as I watched Richard, a man burdened with grief over the recent death of his wife Suzanne, going through the simple rituals of his day job working as a Tennessee fish warden. He works with a small team that sifts waterways for fish, retrieving them and then relocating them. And then, at home, Richard sifts the emptiness of his quiet, spacious house, searching for recurrences of strange phenomena that have made him suspect that Suzanne has come home… as a ghost.

When your house keys move across the kitchen counter on their own, and when lights start flickering without apparent cause… who ya gonna call?

And, more importantly, what will you do if you catch a ghost? Keep her? Let her go?

Yes, Richard (played with endearing solemnity by comedian Jim Gaffigan) is bound to partner with ghostbusters. More specifically, one ghostbuster — a young woman named Shelia (it’s pronounced ‘SHE-la,’ but the character spells out her name S-H-E-L-I-A, and the end credits confirm that spelling). Shelia (Marin Ireland) has worked with paranormal investigation teams before, but happens to be “between groups” right now. She doesn’t necessarily believe in ghosts; she admits uncertainty in the radio interview that opens the film. But she wants to know whether she can believe in them or not. So, when her radio interview gets the attention of Richard’s priest, she soon finds herself taking notes on a possible haunting.

Most mainstream moviemakers would take this premise and head straight for the jump-scares. And, let’s face it — they’d probably also tease us with the potential of romantic chemistry between Richard and Shelia. But Harrill makes no moves to cultivate a love story between them — Richard is too wounded and Shelia is too preoccupied with her own history of losses, and he’s wise to keep them focused. We don’t get a lot of detail about either character — just enough to know that Richard deeply loved Suzanne and longs to connect with her again, and that Shelia’s love life has been a discouraging series of disappointments.

No, this is not, after all, a film about ghosts, although the possibility of a ghost is what brings Shelia and Richard together for soul-searching and friendship. This is a film about daring to risk belief in spite of failures. Shelia is so jaded on the subject of love that she can’t resist interfering in the budding relationship between her son Owen (Josh Wiggins, winningly awkward) and his sweetheart Lucy (the radiant Atheena Frizzell). “I just don’t want you to get hurt,” Shelia tells him. And her attitude has consequences. Soon, Owen is indoctrinated: “What’s the point of falling in love if it’s not going to last?” he asks, much to Lucy’s disappointment.

And yet, for all of her insistence on permanence and certainty, Shelia seems driven to track rumors of ghosts, setting up cameras and microphones, and stalking the shadows of Richard’s house by night, repeating an earnest appeal: “If you want to communicate, let yourself be known.”

She says this so many times that we’re clearly meant to note the irony: Shelia isn’t interested in letting herself be known. That would require vulnerability and the possibility of harm — more harm.

And there’s further irony shouting from the walls of her workplace: Shelia works at a rental car counter at the airport, the company’s name “Alliance” printed in bold all around her. (To deepen the visual metaphors, she has a clear view of the airlines’ luggage conveyors — she regularly watches people claiming their, um… baggage.)

Nevertheless, the most meaningful moments in the movie clearly come when Shelia lets down her guard and opens up to Richard, or when she attends to his awkward testimonies about marriage, failure, and grief.

And young Lucy, meanwhile, is all about knowing and being known: She’s preparing a presentation for school on Japanese tea ceremonies, and in rehearsing it for Owen it’s clear that she’s inviting him into intimacy. (She emphasizes that ceremony participants typically pass through a small door that requires them to kneel — a posture of humility that brings “everyone to an equal level.”)

For all of this talk about making contact with the dearly departed, the movie keeps insisting on the value of the present and attentive. Both involve risk, and both can lead to harmful discoveries. But love is impossible without faith, and faith is risk — it’s a gamble, a choice to live in confidence of something hoped for, a choice to make choices based on things uncertain and unseen. Love leans us forward, a posture that causes a lot of strain and sometimes topples us over.

I lean forward when I see the forested hills of Tennessee engulfed in fog — so beautifully and quietly captured by Harrill’s cameras — so that rise beyond rise is fainter, more uncertain, until the hills vanish into a blur. I remember this view. In 2013, I sat on Lookout Mountain on the border of Georgia and Tennessee, wrapped in a wool coat and scarf, watching a dream of October colors emerge from the mist and then disappear into it again, as if they were mere suggestions, rough drafts of possible worlds that God was painting and then painting over again. I felt like I was present for the making of the world. I felt like I was in that in-between place, of this world and the next. I wondered if this was what it might feel like in the ferryboat crossing from death into life. And, strangely, I found myself wanting to write stories. Ideas were swimming in my imagination with a vividness I hadn’t experienced in many years. Forgive me, I can’t help but use the phrase: In this liminal space, big fish were begging to be caught.

No wonder Harrill sets his distinctive story of ghostbusters in this territory. He knows that here, whether his characters find any ghosts or not, they will be revealed themselves as luminous beings.

Shelia wants to apply scientific instruments to the purpose of confirming the unknown: Her mind wants certainties that she can explain. But when she’s asked about her professional credentials, she furrows her brow and says, “I don’t know what I am.” As Shelia, Marin Ireland (who also makes a strong impression during a fleeting appearance in Martin Scorsese’s The Irishman) gives a performance that reminds me of the great Marion Cotillard. It’s what critics like to call “understated” — she portrays Shelia as withdrawn into herself, uncomfortable with intimacy. She acts with her jaw, which shifts and clenches with tension and discomfort as if always fighting to align what has been offset.

In my notes, I scribbled about two key moments at which Sheila lets her guard down. In both, she is leaning against a bright space with a stark block of deep darkness on the right side of the screen. During the first, she opens up and describes a personal experience that shook her, that cracked her skepticism, that inclined her to believe. And she is right between the light and the dark, the known and the unknown, looking out as if for confirmation. On the second occasion, she leans back into the bright side of the screen and looks upward, as if receiving a revelation in the Here and Now. It may mark a progression — it may not. But in both, in words or in tears, she is open. She is letting herself be known.

Richard, by contrast, is a man of deep emotion; he feels things, but he not strong on making sense of them. Gaffigan’s performance is endearing and modest; he doesn’t go for any Big “For Your Consideration” Moments. He makes Richard seem like a man who has become half-a-ghost himself during the harrowing and hollowing of his loss.

He needs Shelia, and she needs him. Harrill seems to suggest that, for all of the films we see every year that investigate the paranormal, few have even begun to reveal the mysteries of the living, breathing human beings in their foregrounds.

The poet Scott Cairns has written about a word in Greek for which English has no equivalent: nous. The nous, he explains, is “the heart’s intellective aptitude” that lies “dormant” unless we “find a way to wake it.” (Read his poem about it here.) It’s not a sixth sense: Rather, the nous is the place where our mind and heart meet and work things out in a relationship of two distinct human powers. It’s where head and heart develop a common language, and a new way of being is born.

Some movies about ghosts are puzzles for the mind to solve, and others appeal to evoke emotions. Harrill’s movie suggests that the best place for close encounters lies in the space between strangers, and in the borderlands between mind and heart. There, we can commune more profoundly, and know in ways that cannot be reduced to paraphrase.

Regardless of their successes or failures in ghost-busting, Richard and Shelia are “meeting on an equal level” and “making themselves known.” And in their uncertain communion, they are finding new occasions of healing and hope.

These things don’t happen with the typical thunder and lightning of big-screen drama. So, appropriately, Light from Light isn’t the stuff of sensational big-screen crowdpleasers. The work it does is something subtler. When I watched this film with three friends, we didn’t have the rousing rave-fest I had hoped for as the credits rolled. We wrestled with a few lingering questions. And I rashly concluded that I was more puzzled than inspired, honestly. Then we moved on to the more pressing demands of our days.

But that was weeks ago. And very little else in my year at the movies has stayed so vividly on my mind as Light from Light. It’s haunting me. And the more I write about it — I’m going to make myself draw this review to a close now, hoping my nets of words have caught a useful idea or two — the more illuminating the movie and its mysteries become.

You might call this personal reflection “Light from Light from Light.” It’s what I’ve caught in these deep currents, currents that are still in motion.