Finley McCann is an aspiring marine biologist, spending her days watching the ocean she loves die before her feet as the world spins on unmoved to stop it. Three years after a chance meeting with a survivor of a species thought extinct for centuries, Finley stumbles on an opportunity to save a Mer, and shock the world into acting before it's too late. Tell Me How Long is a twist on the modern merfolk myth, and what it takes to survive under the threat of humanity in the open ocean.