The world would be a less stressful place, or at least a less silly one, if clueless people would stop checking into creaky old houses on the edges of dark, forbidding forests — especially an unstable young mom accompanied by her small son. And extra especially if this mom can encounter a crazy old lady who shuffles up to her and her son and screams "It's not your boy!" and somehow fail to accept this as food for thought.

Sarah O'Neill (Seana Kerslake) is an emotionally troubled woman who has arrived with her cute kid, Chris (James Quinn Markey), at a ramshackle fixer-upper she's bought on the outskirts of a small Irish town. The house is gloomy, and the forest nearby is capital-O ominous. Late one night, Sarah awakes and discovers that Chris is not in his bedroom. She makes her way outside with a flashlight and enters the woods. She doesn't find Chris there, but she does come upon a huge, well, hole in the ground — a vast sinkhole about the size of a soccer field, if soccer fields were perfectly round and filled with perilous sand. She still doesn't find Chris and so returns to the house, where she is startled to discover that her son is now present. He wonders in eerie innocence how could she have thought otherwise.

The boy seems different. "There's something not right with him lately," she tells a doctor, who can't find anything wrong with Chris but decides to prescribe anti-anxiety medication for Sarah. He also asks about a small scar on her head — the work of her mysteriously absent husband, perhaps?

Things get creepier. Chris was once afraid of spiders (there's a big one in his room) but suddenly sees them as finger food. The crazy old lady cashes out. Sarah finds her dead on the ground with her head buried in the dirt. At the funeral, the old woman's husband provides Sarah with some spooky backstory. Chris gets frighteningly ... let's say rambunctious. Sarah buys a spy camera. Uh-oh.

The movie is a first feature by Irish director Lee Cronin, who's happy to make it clear where he's coming from; there are modest nods to such genre classics as "The Shining" and "The Blair Witch Project" sprinkled throughout the film. Especially in its first half, the picture feels like a straightforward demon child exercise. But Cronin and his cinematographer, Tom Comerford, keep it fun with lighting and production design that create an atmosphere of rich, smothering dread. Then, in the last third of the film, the story makes an unexpected descent into sci-fi horror, and it pretty much works — which, in the land of very low budgets, is sometimes the Holy Grail.

'Mapplethorpe'

The late art-porn photographer Robert Mapplethorpe is a tricky guy to do a biopic about. Consider one of his most famous photographs, a full-body self-portrait that shows him twisting around at a wall and looking back at us past his naked butt, which has the handle of a bullwhip inserted into it. Mapplethorpe's interests extended to flowers (ravishing close-ups of calla lilies and parrot tulips) and celebrities (from Princess Margaret and David Hockney to such fellow New York pop luminaries as Debbie Harry, Talking Heads and longtime muse Patti Smith). Mapplethorpe's black-and-white proto-punk photo of Patti became the cover of her first album, "Horses"). But most of his reputation is built around the rough-trade erotica that consumed him, especially the prodigiously engorged members of the many gay men he solicited to be his models.

Ondi Timoner, best-known as a maker of probing documentaries ("Dig!," "We Live in Public"), has now taken a crack at telling the Mapplethorpe story in her first non-doc feature. Given the constraints of time (the picture was shot in 19 days) and budget (low), the results are naturally mixed. Timoner scored something of a coup in signing Matt Smith — a longtime star of the neverending "Dr. Who" franchise — to play Mapplethorpe. Smith bears no special resemblance to the artist, but he gives a good account of a man who's found himself in the grip of an obsession he can't entirely understand. Marianne Rendon bears even less of a physical resemblance to Patti Smith; she has a sweet warmth we don't associate with the pop star Patti. But we do find that sweetness in Smith's Mapplethorpe-era memoir, "Just Kids"), and we miss it in the movie when Rendon's not around.

The picture is held back by its overly linear structure. Long Island Catholic boy Robert moves to Manhattan, meets Patti, moves into the Chelsea Hotel with her — bing, bing, bing. It's fun to see the period footage of Times Square with Bruce Lee and Fred Williamson lighting up the marquees and to hear vintage tunes by Bronski Beat and Jobriath along the way, but did we really need the lovebirds' predictable visit to Robert's parents so his father can express his pissy disdain for both of them?

Attracted to the underground bondage scene, Robert suddenly realizes he's gay. "I guess I always knew it," Patti says, sadly packing her bags. Robert discovers that the fine-art photography market isn't quite ready for gleaming photos of gay sex. But then he meets the wealthy collector Sam Wagstaff (a moving performance by John Benjamin Hickey), who becomes Robert's older lover and generous benefactor. Before long, Robert is selling prints for $25,000 a pop. But the age of AIDS has dawned, and one day, Robert gets a heartbreaking call from Sam: "It has arrived," he says. Sam advises Robert to get tested, but he refuses. Robert's brother (and emotional punching bag) Edward (Brandon Sklenar), accuses him of willfully spreading the virus. Robert doesn't care — before he's in a wheelchair, like so many others.

The movie has the virtue of not fudging anything. Gay sex and affection are casually presented, and Mapplethorpe's most hardcore photographs receive unflinching screen time. The picture is a little low on energy, and it would have benefitted from more complex sets and more numerous extras to fill out some of the scenes. Unfortunately, those things cost money.