Lily Gullick lives with her husband Aiden in a new-build apartment opposite an estate marked for demolition. As the area in east London becomes increasingly gentrified, keen birdwatcher Lily is intrigued by the social divide on her doorstep. Soon she is observing the neighbours through her binoculars and regaling Aiden with her take on their daily lives. But when Lily sees something suspicious in a neighbouring tower block, she keeps the information to herself. The following day, the police have cordoned off the entrance to the building after an elderly woman is found dead in her flat. Lily is convinced that what she saw is linked to the death and realises that she has to act. But nobody is listening to her. However her interference is not going completely unnoticed and Lily believes that her own life is under threat. But can she really trust everything that she sees?