The video features a single jellyfish, luminescent in a vibrant magenta or purple hue, gently drifting within a cylindrical aquatic display. The jellyfish's bell subtly pulses, causing it to undulate and slowly move through the water. Its translucent body allows for some internal structures to be faintly visible. The surrounding water and the cylindrical container are bathed in a soft purple light, creating a glowing effect, particularly along the inner surface of the tank which appears to have some reflective or textured elements that scatter the light into shimmering particles. The background outside the immediate illuminated area is dark, suggesting an exhibit in an aquarium or a similar low-light environment. The overall ambiance is serene and mesmerizing, highlighting the ethereal beauty of the jellyfish against the dark, artificially lit setting. There are no people visible, and no discernible text. The scene is likely set in an aquarium, with the provided context indicating Saint Petersburg, Russia.