The video shows a close-up of a person's fingernail painted with black nail polish. The person uses a brush to apply white nail polish in a marbled pattern on top of the black polish. The brush strokes are deliberate and create a swirling effect. The person then uses a different brush to drag the white polish through the black polish, creating a marbled design. The video ends with the person using a brush to clean up any excess polish around the edges of the nail.