Future Films is backing the project. Ellen Wander at Film Bridge International is handling world sales.
Costa Theo and Joy Mellins at Milcoz Films are producing with Peter La Terriere, who now works in-house at Future Films.
The story follows a young woman, mourning her father, who leaves New York to work in a country hotel where she finds a hellish world.
A January shoot is scheduled in North Carolina, as Future Films continues to cash-flow US tax credits.
Murphy, star of 8 Mile and Sin City, is represented by David Unger at ICM.
'Every time you write a script you can't help but imagine someone in the role, in the case of 3:30am it was Brittany Murphy and only her,' Davis said. 'She has the range, the charisma and the intelligence I need for this very complex character. It's a director's dream come true, when you get the actor you want.'