A washed up true crime writer and his family move into a new house where he begins work on a story that he hopes will resurrect his career. After finding a box of super 8 film reels and a projector in the attic, he discovers that the reels are snuff movies, and that he and his family could now be in grave danger.
Taking inspiration from stuff like 8mm and various supernatural chillers, this is a surprisingly solid and effective horror film. While there are scenes of violence, it's not a gorefest, and, amazingly enough trades more in mood and atmosphere to deliver the scares over showing lots of bloodshed. I mean, there is violence, but they only show just enough to get the point across, and more importantly, use it as punctuation to a build up.
There are jump scares, maybe like a handful or so, but for the most part, they work well. Some fall flat, but they most work. One of the crucial elements that really makes this film genuinely eerie and creepy is the music. It's super moody, and pretty groovy. The cinematography is also quite good, and I loved the incorporation of the super 8 footage, though from a story perspective, I'm not sure why it had to be this specifically.
Another nitpicky kind of gripe I have is the film's title. Why call it this? The word sinister isn't said in the movie, but I guess it does fit, if you look at the nature of what happens as being sinister. Other than that though, they could have gone with a better title.
The performances are fine, and the film is well cast. The characters are generally pretty smart, and there are arcs and development, so that's good. The film is generally pretty well written and thought out, and I appreciated that it didn't come off as stupid or dumbed down.
All in all, this is a pretty successful film. It's creepy, fairly intense and disturbing at times, and genuinely quite compelling. Give it a watch.
P.S. There's also a pretty sick sense of humor in places too, which I thought was kinda funny.