This is a game movie of Black Mirror with no commentary. You get all the story related cutscenes and gameplay so you won't miss out on anything. Gameplay that doesn't add anything interesting or is unrelated to the narrative is edited out to keep the story moving.
Official Black Mirror summary:
Scotland, 1926. Following the death of his father, David Gordon visits his ancestral home for the first time in his life. A life that is soon threatened by the dark secrets that claimed the sanity of many Gordons before him. Black Mirror Castle demands an offering.
Capture device: Elgato HD60