They enter through an airlock and meet Aximili-Esgarrouth-Isthill. They abandon ship and morph to dolphin when they are in range and discover the dome of an Andalite Dome Ship deep beneath the ocean's surface.

The Andalite's location is too far from the shore for the Animorphs to reach under the two-hour morphing limit, so they (except Tobias) morph into seagulls and stow away on a large container ship (called the Newmar, from Monrovia, headed towards Singapore) that is heading in the right direction. They also figure out that Visser Three could be receiving the message and that the Yeerks are probably looking for the lost Andalite as well. They decide that the distress call is connected to the morphing ability, and Cassie and Tobias feel it the strongest because Cassie is the most in control of her morphing ability and Tobias is trapped in a morph. Cassie has a feeling that this place is of Andalite origin, and the Animorphs wonder if Cassie's and Tobias's visions are a sort of distress call from an Andalite trapped in the ocean. The whale speaks to Cassie through song, telling her about a strange place of grass and trees under the ocean. Marco is able to morph back to his human form, and the whale, grateful, saves him from drowning. The Animorphs fight the sharks and drive them off, and Marco is nearly killed in the process.

While out in the ocean, they find a humpback whale under attack by a group of sharks. The Animorphs decide to investigate, and acquire dolphin morphs to do so. Jake sees a news item on television about debris with what looks like Andalite lettering on it that has washed up on the beach, and when he shows it to the others, Cassie and Tobias have such strong visions that they momentarily pass out. Cassie and Tobias are having strange dreams about a presence in the ocean.

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