 She tries to run from Jackson leading him around the maze of corridors and rooms.Her voice echos around the building as Jackson pursues her in desperation as he catches up with her he falls to his death through a hole in the floor Niamh had stumbled across before when she was looking for respirators.We discover in flashbacks that Niamh was suffering depression and had drugged her children and then tried to drug herself unsuccessfully, her children dying as a result.