Smoke and Mirrors

Karen Gillan in Oculus

Every kid has talked to the mirror, and every actor has bounced lines off it. For Oculus, Karen Gillan treats her reflection not just as a rehearsal partner, but as a source of pure evil. "It's like going back to my childhood," she said. "It's all perception. What's real, what's not."

The new horror movie from Blumhouse (producers of Sinister and the Paranormal Activity franchise) casts the star of long-running British sci-fi show Doctor Who as orphaned Kaylie. Along with her brother Tim (Maleficent's Brenton Thwaites), she faces the menace of a possessed mirror – one they blame for the deaths of their parents (Battlestar Galactica's Katee Sackhoff and Rory Cochrane of 24 and Empire Records).

Writer/director Mike Flanagan admits the idea of a monstrous reflecting glass was a hard sell. He said, "One of the running jokes from the initial exposure out into the studio world was, 'Does it have to be a mirror?'" Immobile objects aren't obviously threatening, but then buildings don't move much either, and that never hurt classic ghost stories like The Haunting and The Legend of Hell House. Referencing The Shining, Flanagan described the mirror as "a portable Overlook Hotel, because you can pick up your monster and move it into a new house and a new home."

In fact, he's stared into the mirror before, in a 2006 short. The format was similar: A man (Scott Graham), convinced his father was driven to murder by the mirror, tries to catch its demonic intentions on camera. Aside from being Flanagan's calling card film, it became a proof of concept for the feature. He said, "I don't know whether we could have done [Oculus] without the short, to prove that, yes, it can be unsettling, and yes, the fact that it's a common object, a ubiquitous object, will work in our favor." When he started the adaptation process, he knew there were endless new stories to be found behind the glass. "Its interaction with people would be as unique as their own reflection." In fact, he ended up with nine potential stories, "and we just went with the one with the history built in."

That history is contained in one monologue, delivered by Kaylie. According to Flanagan, shooting it was "easily and by a mile the most challenging part of that movie. One of the reasons campfire stories work is because there's no external stimulus. Everything's dark, you've got your light source right in the center, and you can focus on the story itself." When Flanagan started laying out the scene, he wanted to maintain that feeling of firelit dread, "so we're not distracted by everything that's going on in the movie, so that we can just sit and listen."

Gillan had a different challenge: memorizing a 12-and-a-half-minute ghost story and repeating it over and over again across a two-day shoot. She said, "If you think of the memory as a muscle, I pulled it doing that, and I couldn't learn lines properly for two months after that." Fortunately, the script has lots of tense near-silent scenes – or, as Gillan called them, "the scary looks. I'm good at that."

Strip away the haunted mirror, and Oculus is really a family drama, For most of the shoot, Gillan was sealed in the house with Thwaites, and the pair bonded as outsiders on an American set. She explained, "He's Australian, I'm Scottish, we're in Alabama, so we were like, 'Where are we?'" It also gave her an opportunity to work with Sackhoff as her tormented mother – a rare bonding experience for two performers who made their reputation in major genre series. "She's really inspirational to me, because she's an actress who has worked on a really iconic sci-fi show, and has made the transition to really amazing film work, and still does really good television," said Gillan. "That, for me, is living the dream."

It also meant dream casting for Flanagan, who not only is a fan of both Battlestar and Doctor Who, but also – in an eerie coincidence – had used Sackhoff as an inspiration for Kaylie. He said, "When we decided, 'OK, we're going to have a strong female lead, rather than a guy in the room,' we had a picture of Katee on the wall."

Oculus opens Friday, April 11. For a complete review and showtimes, see Film Listings.