“Oculus,” a thriller about a haunted mirror that can possess anyone who gets near it, stars Karen Gillan (“Doctor Who”) as a woman trying to clear her father (Rory Cochrane, “Argo”) and brother’s (Brenton Thwaites, “The Signal”) names by proving something supernatural exists in the mirror.

The film takes a while to get going, but once it does it hits on all cylinders. It’s suspenseful, it’s gory and it has a lot of twists and scares. The use of flashbacks to tell the story of when the characters were children was a very effective technique in the film. The seamless transitions from the past to the present work really well and both stories are woven in an interesting manner.

Gillan and Thwaites have good chemistry and are fairly believable as an estranged brother and sister duo. They are as impressive as their younger counterparts, played by Annalise Basso (“Bedtime Stories”) and Garrett Ryan (“Insidious 2”). They do an excellent job of portraying these characters at a young age. Gillan and Thwaites do passable American accents considering Gillan is Scottish and Thwaites is Australian.

The film really keeps the viewer guessing, which made it an enjoyable ride. It takes you in interesting and unknown directions. A large chunk of the movie will have you questioning what is real, and once the mirror finally starts doing its haunting, it also keeps you guessing on what it’s going to do next. Even though you kind of know what happened in the past, it still keeps the audience on the edge of their seats for the majority of the film.

Director Mike Flanagan (“Absentia”) does a great job providing thrills and horror. There isn’t too much reliance on horror movie clichés. Yes, the monster in the mirror has been done before, but there is a new twist on it that feels original. He gives quite a few interesting shots that help build the suspense. He manages to keep the audience unsure of what is real and what isn’t.

The movie doesn’t shy away from some more disturbing imagery, but for the majority of it there isn’t much that is scary. At the halfway point, the actual scary parts come. The beginning was a bit too slowly paced and bogged down in exposition, which felt unnecessary when we got to see so many flashbacks.

The backstory on the mirror, however, is intriguing, and as Gillan’s character explains the mythology of the mirror you get sucked into it. They find an effective way to tell you about the devastation this mirror has done. Gillan’s character is actually the kind you can root for in a horror film. She’s prepared to go up against this mirror, which she planned for eleven years.

“Oculus” had characters that you actually wanted to succeed. It had the right amount of gore and the right amount of suspense. The story was intriguing and didn’t feel like it borrowed too heavily from any other horror films. The film did an amazing job of playing mind games on the audience right until the very end.