Katie Firestone is a marine biologist who is a friend of George Fayne.
In 2003, George and Bess set up a vacation for Nancy to go stay with Katie on her whale watching boat. However, they discover it has been vandalized upon Nancy's arrival, and Katie cannot get it to work. As Nancy investigates, she learns that Katie had strongly advocated for the lone orca whale that had showed up to be studied the previous night (much to the dislike of harbormaster candidate Holt Scotto), even though she had been secretly feeding it.
At the end of the game, Katie's boat is hijacked when she finally gets it working again and Nancy rides with Andy Jason into the harbor. She finds Katie tied up on the boat used to smuggle sunken animal furs, but Holt and the coast guard come to their rescue. Katie ends up voting for Holt after all.
- "Besides, I've got my very own private detective now, you."