This 3D animation symbolically explores the invasive nature of the upside-down jellyfish (Cassiopeia) through the motif of a red line. Inspired by the words of Dr. Claire Rowe, her narration becomes the sole text and driving force of the piece. Set within an underwater 3D environment, the surrounding coral reef is intentionally designed in 2D, creating a layered, dreamlike tension between depth and flatness. As the red line moves through this hybrid world, it embodies the subtle yet pervasive spread of invasion. The animation blends visual metaphor, texture, and sound to express the fragile balance of marine ecosystems.