A tense psychological thriller with a simple premise, complex emotional undertones and a chilling twist ending.

Writer Christina Hodson says the inspiration for Shut In came to her while she was living alone in a creaky New York City studio apartment. Imagining the possibilities behind the unexplained noises she heard late at night, the first-time screenwriter penned the script in just six weeks.

 Shut In is a heart-pounding thriller starring Naomi Watts as a widowed child psychologist who lives an isolated existence in rural New England. When a young boy Mary (Watts) is treating goes missing, and is presumed dead, she becomes convinced that his ghost is haunting her and her bedridden son.

“I wanted to turn the tropes of the genre on their heads,” says Hodson. “And I wanted to leave little clues along the way so that when you do realize what’s happening, you’ll be able to go back and it will be satisfying.”

Executive producer and Lava Bear president Tory Metzger was immediately impressed by the script, which she says was unlike anything she’d read before. “If you do what I do and read a lot of screenplays, you often think you know where they’re going — and very often you’re right. In this case, I had no idea what would happen. One of the things that struck me was that I was 60 pages into the screenplay before I actually understood that instead of a great dramatic movie, I was reading a genre script. That’s not an easy thing to do.”

Metzger says she and former Lava Bear CEO David Linde, who also serves as an executive producer on the film, were excited to find a script with such a strong female lead character. “It was a great part for a woman,” she says, “and that’s something that we’re always on the hunt for, because there are so few of those out there.”

Concerned that the screenplay’s subtle dramatic elements would be lost in the hands of a filmmaker who wanted to make it “just another shock-horror movie with a lot of jump scares and loud bangs in the night,” Hodson says she and the producers were keen to find the right director for the project.

Enter Farren Blackburn, an experienced British television director with a strong minimalist vision for Shut In. “He understood the film unlike any of the other directors we had spoken to,” says Metzger. “We had some very experienced and, in some cases, award-winning directors who were interested. But there was something about Blackburn’s connection to the material — and in particular, his understanding that less would be more — that drew us toward him.”

Blackburn says he was intrigued with what he saw as the cinematic potential afforded by the script’s economical storyline and confined setting. “When I first read Shut In, I was excited by the fact that it was a genre movie that could be very beautiful and shot with great artistry,” he says. “I’m a big fan of those pared-down ’70s American movies that had a European aesthetic. Plus, Shut In has a protagonist you really care about and who has an interesting journey, so for me it was a no-brainer.”

To play the film’s central character, a once happily married professional woman who finds herself in increasingly desperate straits in her own rural New England home, the filmmakers turned to two-time Oscar® nominee Naomi Watts.

The British actress, whose career began in Australia before moving to the U.S., says she was attracted to the challenges of capturing Mary’s fragmented state of mind. “She is completely consumed with taking care of one person, and not really relating to anybody in the outside world,” says Watts. “I think she’s shut down, emotionally. And as much as she wants to care for her child, it’s difficult for her. She struggles with it, and that’s when you see her starting to have these nightmares and weird things playing out in in her mind. The resentment of how her life has changed creeps in.”

Also appealing to the acclaimed actress was the simplicity of a story centered almost entirely on two characters and the dramatic change in Mary’s emotional state before and after the crash that leaves her husband dead and her stepson catatonic.

“When we meet her in the beginning of the film she seems to be happy,” Watts observes. “Then, we see her in a whole different way a few months later — she’s lost her husband in this horrific car accident, and her stepson is now in a vegetative state, in a wheelchair, and completely dependent upon her. Her whole life becomes about catering to his needs.”

Terrified by nightmares that eventually spill over into her waking life, Mary turns to her supervising therapist, Dr. Wilson, for help sorting fact from fantasy.

“Quite often, a shrink has a shrink,” observes Blackburn. “Dr. Wilson is someone that Mary confides in more and more as her life starts to unravel. He has an open mind, but he tries to convince Mary that the visions she’s having are simply dreams and nightmares resulting from her exhaustion.”

The role is played by Oliver Platt, one of Hollywood’s most in-demand supporting actors over the last three decades. “He is fantastic,” says Blackburn. “I’m a big fan of his. Lake Placid is one of my guilty pleasures. I don’t talk about it too much, but I love that movie. And I’ve loved him ever since I first saw him in that.”

In the years before and since he appeared in that 1999 David E. Kelley-penned horror comedy, the versatile Platt has been seen in dozens of movies and TV series, including Frost/Nixon, X-Men: First Class, “The West Wing,” and “Chicago P.D.”

“Oliver Platt brings a real presence and charisma and gravitas to the role,” says Blackburn. “He has an amazing reveal in the movie, which is something that I know really appealed to Oliver. I can’t say what it is, but he has a real standout moment in the latter half of the movie.”

For the majority of Shut In, Dr. Wilson communicates with Mary through Skype. As Wilson advises his patient, and her mental state seems to be further deteriorating, their exchanges are tinged with a palpable sense of helplessness.

“It’s a really clever narrative device for this story, because not only do a lot of therapists have supervisors, but in this case, she’s just experienced trauma herself,” Platt says. “And so it’s a loaded relationship, therapeutically.”

Watts similarly found a lot of dramatic potential in her character’s online sessions with Dr. Wilson. “She’s playing out all of her demons in her nightmares, and she’s starting to hear noises, and she can’t tell if they are dreams or reality,” she says. “When we see these phone calls take place via Skype throughout the movie, she’s expressing her fear and the fact that she’s possibly losing her mind. That vulnerability comes through in those scenes with her doctor.”

Platt says he was excited to work with the actress, particularly in a psychological thriller, a genre she has become known for. “It’s sort of a classic Naomi Watts role,” he says. “Naomi has got such wonderful instincts, and she’s become one of the great modern women in peril. I admire her so much because she always takes us along for a serious ride.”