Nemo’s mom, Coral, was killed by a barracuda.
The opening scene for Nemo reveals that Nemo’s mom, Coral, was killed by a barracuda. The film portrays this as making Marlin more protective of his son, which leads to the events in the movie.
This scene is a light-hearted introduction to the main conflict of the film. It sets up the journey that Nemo and Marlin will have to go through throughout the film. We also get a quick introduction to the protagonist, Marlin, who is in a frenzy to get his son back to safety.