On the night of the experiment, a wild storm rages outside as they set up in a cave underneath the house. Margaret tells her father that Tera will not possess the mummy cat and will remain powerless until the experiment is complete, seeming to confirm that Margaret has been possessed. Somehow comforted by the confirmation of Tera's existence, they proceed with the experiment and unwrap the mummy. They discover that Tera is wearing a marriage robe, which greatly distresses Margaret. Malcolm is put in charge of turning on the electric lights after the experiment ends, and Margaret blows out the candles. As the lamps are lit, the coffer begins to glow, emitting a green vapour that passes into the sarcophagus. Suddenly, the wind from the storm shatters a window, blowing the vapour around the room, and black smoke pours out of the coffer. The room is engulfed in smoke, and Malcolm waits for the command to turn on the lights, but it never comes. The lamps slowly burn out and Malcolm fumbles in the dark, coming across the limp body of a woman whom he believes is Margaret. He carries her upstairs and leaves her in the hall while he runs for matches, but when he returns, he finds only Tera's bridal robe lying on the floor, the Jewel of Seven Stars lying where the heart would be. He returns to the cave and turns on the lights to find all of his companions on the floor, dead.