Maddy (Amandla Stenberg) is a smart, curious and imaginative 18-year-old who is unable to leave the protection of the hermetically-sealed environment within her house because of an illness. Olly (Nick Robinson) is the boy next door who won't let that stop them from being together. Gazing through windows and talking only through texts, Maddy and Olly form a deep bond that leads them to risk everything to be together, even if it means losing everything.

When Maddy finds out she's not sick, she flys to NY to be with her true love Olli. What will she get upto in her new life.