The Uninvited invites you in. All images © 2008 DreamWorks LLC and Cold Spring Pictures. All rights reserved. Courtesy of CIS Vancouver.

On the line between a psychological thriller and a horror film is where you'll find The Uninvited (opening today from DreamWorks/Paramount), which marks the feature directorial debut of The Guard Brothers. The duo of Tom and Charlie Guard is well known as a commercial directing team, but The Uninvited shows off their storytelling skills, and it introduced them to the visual effects artists at CIS Vancouver.

"Like most commercial directors they have a real sense of framing and art direction," observes CIS Vancouver Visual Effects Supervisor Bruce Woloshyn. "And that, coupled with their ability to tell a story, made it fun. There's some gore in this movie, but the movie's not scary because of the gore. The movie is scary because you're unsure about what's really happening."

In the tradition of The Sixth Sense and A Beautiful Mind, The Uninvited manipulates point-of-view and plays with the audience's perceptions of what's real and what's imagined. Based on a 2003 South Korean horror film, A Tale of Two Sisters, the film largely unfolds at an island waterfront estate. It follows the return home of Anna (Emily Browning) after her release from a psychiatric hospital. She's intent on learning about the circumstances of her mother's death and a troublesome new romance of her father (David Straithern).

"VFX-wise, it's a relatively small picture," admits Woloshyn, a veteran supervisor whose credits include Night at the Museum, Stargate: Atlantis and Smallville. "Visual effects were there to help drive home story points and heighten things a bit."

A dramatic moment with an actress climbing out a window had to be greenscreened so the performance could be captured up close.

Woloshyn first met the Guard brothers during principal photography on Bowen Island, British Columbia, and was impressed. "They think aloud in a sense, because they're talking to one another. I had an understanding of the way they saw things because my background includes editing commercials." At the time of shooting, Woloshyn was committed to finishing a television series, so most of the film's on-set supervision was handled by Woloshyn's longtime colleague Steve Hodgson (Vantage Point, The L Word).

"The Uninvited is what I would call a complete compositing movie," Woloshyn observes. "Having been a compositor for a very long time, I felt we could shoot all the parts and do it all in comp. I was more comfortable taking that approach in order to turn things around quickly. Even when you're doing CGI, I'm a huge believer in starting with live action photography. Shoot as much as you can, because it makes the CG that much better."

Woloshyn and his nine-person crew at CIS Vancouver knew from the start that they would be shooting a greenscreen scene showing an actress climbing out onto a rooftop. "It was too dangerous to put the actress on top of the roof of a house that sits on a cliff," he remarks. "So a little section of the roof was rebuilt on a stage. There was a lighting consideration too, because it was a night shot and we wanted to cheat the depth of field so that she stood out a little bit better. Greenscreen was the economical way to do it."

It's also a dramatic moment when she leaves the room and goes out on the roof, so we wanted to use the real actress," Woloshyn adds. "You don't want to do that with a stunt performer or you'd have to shoot it wider."

CIS Vancouver was additionally tasked with putting a helicopter into a POV that they didn't have, and doing sky replacements as well. The latter, says Woloshyn, "Is where the Guard brothers' commercial background comes in. There was one shot where they waited for the light to get better. Then they shot the scene and let the actors go and the light turned even better. So they rolled some more and we combined the multiple takes. That kind of work is not confined to Mr. Lucas!"

A key moment in the film arrives when Anna is sitting in a restaurant, observing a girl seated at the bar holding a glass of milk. The girl turns around and drops the glass, and as it hits the floor the milk turns to blood. Woloshyn explains, "This was a really simple trick because we shot multiple takes at a high frame rate and cleaned the floor a lot. Then we did a fancy articulated split between different plates. We did quite a bit of rotoscoping [using Digital Fusion] because we needed to hold pieces of the shattering glass from the milk pass."

CIS Vancouver's Lead Digital Compositing Artist, Brian Fisher (Changeling, Sin City, The Aviator), cut parts out so that the glass looks like it's the same glass throughout the entire shot. Woloshyn notes, "Then to give us better interaction, we've got some particle enhancement that was built in Digital Fusion. It was a particle system that we could put inside the blood so that the blood splattered properly."