Sixteen-year-old Lara Jean Song keeps her love letters in a hatbox her mother gave her. They aren’t love letters that anyone else wrote for her; these are ones she’s written. One for every boy she’s ever loved - five in all. When she writes, she pours out her heart and soul and says all the things she would never say in real life, because her letters are for her eyes only. Until the day her secret letters are mailed, and suddenly, Lara Jean’s love life goes from imaginary to out of control.

Belly measures her life in summers. Everything good, everything magical happens between the months of June and August. Winters are simply a time to count the weeks until the next summer, a place away from the beach house, away from Susannah, and most importantly, away from Jeremiah and Conrad. They are the boys that Belly has known since her very first summer—they have been her brother figures, her crushes, and everything in between. But one summer, one wonderful and terrible summer, the more everything changes, the more it all ends up just the way it should have been all along.

Overworked and underappreciated, single mom Amy Byler needs a break. So when the guilt-ridden husband who abandoned her shows up and offers to take care of their kids for the summer, she accepts his offer and escapes rural Pennsylvania for New York City. Usually grounded and mild mannered, Amy finally lets her hair down in the city that never sleeps. She discovers a life filled with culture, sophistication, and - with a little encouragement from her friends - a few blind dates.

In the Land of the Rising Sun, where high culture meets high kitsch, and fashion and technology are at the forefront of the First World's future, the foreign-born teen elite attend ICS - the International Collegiate School of Tokyo. Enter foster-kid-out-of-water Elle Zoellner, who, on her 16th birthday discovers that her long-lost father, Kenji Takahara, is actually a Japanese hotel mogul and wants her to come live with him. Elle jets off first class from Washington, DC, to Tokyo, which seems like a dream come true.

After the loss of her mother and her own battle with breast cancer, Joanna Teale returns to her graduate research on nesting birds in rural Illinois, determined to prove that her recent hardships have not broken her. She throws herself into her work from dusk to dawn, until her solitary routine is disrupted by the appearance of a mysterious child who shows up at her cabin barefoot and covered in bruises. The girl calls herself Ursa, and she claims to have been sent from the stars to witness five miracles.