Dweller (2021)

For ten years, Pete has lived a lonely solitary life locked securely inside a bunker. His well honed routine and solitude is shattered with the sudden, unexpected arrival of Sophie, a mysterious visitor who knows much more about her surroundings than she lets on. Sophie's arrival coincides with a strange awakening in the bunker where they are as systems begin coming to life without warning. It quickly becomes clear that Pete and Sophie are not alone in the bunker and something malevolent is stalking them through the corridors.