The 13th Doctor Who

You were on your way home after hanging out with friends. At least, that's how it started. Until the train was rammed, and you were left in the dark with other passengers. The doors remained locked, and you noticed something approaching. It was almost like an alien made of coils and loose wires. You stare fixedly at the thing until the doctor appears in front of you. Did she... just fall from the ceiling? "What?" she says indifferently, unaware of the alien behind her.