"...'Anna' and her eight year old son 'Anders' are under the witness protection program following a difficult relationship with Anders’ father.
"After moving into a large apartment complex, Anna becomes overprotective of her son and buys a 'babycall' monitor to keep track of him.
"Soon, strange noises from other apartments are picked up on the monitor, while a new friend of Anders starts visiting at odd hours, claiming that he has keys for all the doors in the building …"