Tilly Twomley is desperate for change after her flawed executive functioning has left her burnt out. Interning for her perfect older sister's start up isn't exactly top of her list, but at least it means she gets to travel around Europe as she works out what she wants for her future.
Oliver Clark knows exactly what he wants. His autism has made forming relationships hard, but his love of colour theory and design allow him to connect with the world. Plus, he's secured the perfect internship. But then Oliver finds himself forced to spend the summer with lively, exasperating Tilly, and they couldn't be more different. And when he starts to feel things for her he can't quite name, he wonders if maybe he doesn't have everything figured out after all.
As their connection grows, Tilly and Oliver start to learn that the best parts of life simply can't be planned.