In an Instant is an intriguing erotic novel about a middle-aged woman named Brandy and her friend group, the "nifty fifties," who often get together to commiserate about their love lives. One day, Brandy's ordinary life takes an adventurous and fantastical turn as she is walking along the beach. There, she is drawn to the sea by Triton, the son of the Greek god Poseidon, who whisks her away and leads her on a journey of finding sexual pleasure.