Though credited as producer, John Carpenter described his involvement thusly: "I come in and say hello to everybody. Go home."
Selma Blair did almost all of her own stunts. For her underwater scenes, she spent 12 hours in a water tank, with only short surface breaks, for two days straight.
Rupert Wainwright's last directorial feature that's a theatrical film, as the critical and financial failure of the film led to his film directing career dying.
Tom Welling's character, Nick Castle, is named after Nick Castle, the actor who played The Shape in John Carpenter's Halloween (1978).
In between takes in Vancouver, press were granted access to the set. During Selma Blair's interview, director Rupert Wainwright made a joke she didn't like. In response, Blair reached into her shirt, pulled out a rubber breast enhancement pad, and flung it across the conference room at the director, deadpanning, "That's the Adrienne Barbeau part of the role."