Nineteen-year-old Sydney has the perfect summer mapped out. She's spending the next four and a half weeks travelling through Europe with her childhood best friend Leela. Their plans include Eiffel Tower selfies, eating cocco gelato, and making out with très hot strangers. Her plans do not include Leela's cheating ex-boyfriend showing up on the flight to London, falling for the cheating ex-boyfriend's très hot friend, monitoring her mother's spiraling mental health via texts, or feeling like the rope in a friendship tug of war. In this hilarious and unforgettable adventure, New York Times bestselling author Sarah Mlynowski tells the story of a girl learning to navigate secret romances, thorny relationships, and the London Tube. As Sydney zigzags through Amsterdam, Switzerland, Italy, and France, she must learn when to hold on, when to keep moving, and when to jump into the Riviera...wearing only her polka dot underpants.