Mum & Dad (2008)

Mum and Dad and their 'adopted' children, Birdie and Elbie, work at the airport and live off whatever they scavenge from cargo holds, offices, and hotels--including a steady stream of transient workers who populate the airport's soulless hub. When Lena, a young Polish office cleaner, is befriended by Birdie, she gets drawn into a nightmarish world of torture, murder, and perversity. Imprisoned in a suburban House of Horrors and designated a 'Mummy's Girl', Lena's only options appear to be to become part of the family--and join them in their insanity--or die.