This is book 2 of the "Young Wizards" series.

This note contains spoilers for the book.

Second adventure of Nita and Kit, young wizards.

There needs to be a major ceremony off the east coast to keep the plate tectonics and things in order. The senior whale wizard has just been killed by a whaler, and the apprentice is trying to put through the singing of the song needed.

It's a repeat of a very old and very powerful ritual. Kit and Nita are vacationing by the sea, and get roped in. Nita ends up volunteering to sing one of the parts (in whale form), not originally realizing that means she dies. Oops! Always be sure you understand what you're agreeing to!

Reneging on this would be disastrous personally and globally, so she plans to go ahead with it.

In the end, the Master Shark, who isn't exactly an avatar of the Lone Power, takes that role from her.