Annie MacLeod grew up on a sailboat in the Pacific Northwest, swimming with sea creatures alongside her parents and best friend Evan. After a tsunami, she rescues a wordless man named Walker who emits a hum only she can hear. Their connection is electric. Walker’s touch gives Annie visions of the ocean’s hidden world, a life she’s never known but feels inexplicably drawn to --- yet Evan, the steadfast love who has always been there, remains on dry land. Annie is torn between Evan’s grounding presence and Walker’s magnetic secrets. But then Walker vanishes. Six years later, Annie has buried the past --- until Walker’s otherworldly sound returns, pulling her back toward the ocean. The truth under the water is more ancient than she ever could have known, and Annie must confront a choice that will test her heart and determine her future.