After her father gets a position as high priest in the Esoteric Order of Dagon, Asenath Carlson moved from Leeward, Michigan, a Deep One colony to Innsmouth. Asenath isn't an ordinary girl, she is a Deep One hybrid who grew up in a cult all of her life and her body is going through many changes as she transforms into a hideous sea monster. While she is in Innsmouth she meets, Callista, Kelsey, and Sadie and together they form a group called the Sisters of Mother Hydra. Asenath is reluctant to become a Deep One and longs to be ordinary and keeps getting messages from Dagon. Will Asenath ever learn to accept her fate as a Deep One and take the Third Oath or will her transformation be too painful for her to handle?