Adysson Townsend spends her nights as a siren and days as a human. She owns an ice cream parlor along the waterfront and challenges a big fishing company over their illegal activities. But she's almost out of time. On her twenty-fifth birthday, she must decide which form she'll keep. It's simple until a handsome officer comes to town and steals her heart. Commander Benjamin Yeates volunteers for the job in Maine. Ever since he spotted a mermaid as a youth, he's been curious about Mystic Cove. Now a marine biologist, he jumps at the chance to find out if they're real. He falls hard and fast for Addy before he discovers there's more to her than meets the eye, depending on the time of day...