One line summary: Two couples fail to resolve their issues; no supernatural elements.
Four friends travel to Suffolk, England to see the house that Emma's grandfather lived in. At the center of this is a large, old tree that has a large hollow section, where evil supposedly resides; this tree scared Emma when she was a girl.
At 1:55 into the film, we learn that all the protagonists die, and that we are going to have to suffer through footage from the handheld camera found at the scene. At this point, I only watch this picture so as to complete this review. As a consumer, I would reject the movie and move on to another, better one.
The policeman from East Anglia does some of his own camera work in describing the tableau after all the principals have been hung by the neck until dead. He shows a lot of this huge old tree, including the opening of a huge hollow (film title). The tree is devoid of foliage at this point.
We skip back in time, and start at the beginning of the found footage.
Emma, James, and Scott travel by car to a train station, where they pickup Lynn.
While continuing to their destination, they kill a fox. They stop, and Emma sees the massive old tree and remembers her fear. Her mother had a particularly creepy story about it, which is told later. The tree is in leaf, and looks rather vigorous.
The cottage had been in Emma's family for generations. While going through papers they find news clippings in her grandfather's belongings dating from 1650 to three days before he died. The common thread is suicide of couples by hanging from the tree.
They talk to a local clergyman, who will not tell them anything. A local fisherman recounts two versions of the first suicide. Scott finds a book where an entire chapter is devoted to the tree and the suicides, notably 9 in a period of 18 months around 1983.
The four have other issues. James and Emma have known each other the longest, but were not right for each other. James cannot quite accept that. Lynn definitely draws Scott's attention. Lynn has a child, Kyle, by James, but James and Lynn are not married. What could go wrong there?
Doing recreational drugs seems like a mistake, in any case, but given all the suicide build up, this is a perfectly stupid move. After they work themselves up, they go out in public yelling and screaming. Brilliant. Then they go driving while under the influence. Doubly brilliant.
Emma decides to go back to the cottage herself after Scott gets the car stuck off road. She needs her inhaler, but probably cannot get to it. She heads to the tree for some reason. James catches up with her inhaler, and gets her pointed back to the others.
Scott challenges the tree in the dark. How dramatic. Scott and Lynn start making out in the blackness; James catches this. Emma defuses it, somewhat.
The next day was to be the last day in the area: turn in the keys and leave. Things are broken here among the couples. The local clergy insists that avoiding the tree is the right thing to do, so the history of hangings won't be resolved. Going home, forgetting this place, seems like the clear decision.
They don't do that. The last 20 minutes felt like 200; heavy breathing and screaming in blackness.
Cinematography: 0/10 Found footage. This is better than most; fairly long segments of the first half of the film are in color. The second half is a different story.
Sound: 4/10 As with many dreadful 'found film' projects, sound was recorded. The repetitive sound of the wind screen wipers, for instance, is of exactly zero interest to most viewers especially with the camera focused on uninteresting objects during travel in a car. Listening to James breathing as he walks around confused or scared did not heighten tension. Video footage of a fly on the inside of the car's wind screen was the topper: James' finger impacting the screen and the fly moving about in agitation. Wonderful use of the viewer's time. Some of the yelling overloaded the video camera's ability to record. The breathing in near darkness gets really annoying after a while.
Acting: 2/10 Get a bigger budget and hire better actors next time.
Screenplay: 0/10 At least 50 percent of the film is spent on couples fighting verbally. Perhaps 15 percent is recorded in blackness with barely useful sound. Another 10 percent is focused on auto ceilings, fidgety knees, or the ground. Who cares about any of these three categories? What does this have to do with horror? with thrillers? with mystery?