Christine and her husband Barry have purchased an old house in need of renovation in a small town, using her recent inheritance. They hope that refurbishing the house and starting anew will aid Christine in recovering from a recent near nervous breakdown. Unbeknownst to Christine, her sister Lisa, whom she has invited to live with them, is having an affair with Barry. Barry, a police detective, remains with Christine solely for her money and is seeking a way to eliminate her from his life permanently. Lisa enjoys flirting with Barry right under Christine’s nose, relishing the excitement of potentially being caught. During their renovations, they discover a hidden room in the basement laundry area, sealed with a heavy titanium door adorned with a cross and mystical symbols, locked by a complex mechanism. They make light of the situation, using humor to mask their growing fear that something dreadful might be concealed within.