In the video, a marshmallow is being roasted over a fire. The marshmallow is skewered on a stick and is held over the flames. The fire is licking the marshmallow, causing it to turn brown and black as it roasts. The marshmallow is slowly turning into a crispy texture, and the flames are dancing around it. The video captures the process of roasting the marshmallow in detail, showing the transformation of the marshmallow from a soft, white treat to a crispy, caramelized snack.