Young musician Zach Sobiech discovers his cancer has spread, leaving him just a few months to live. With limited time, he follows his dream and makes an album, unaware that it will soon be a viral music phenomenon.

Seventeen-year-old Stella spends most of her time in the hospital as a cystic fibrosis patient. Her life is full of routines, boundaries and self-control — all of which get put to the test when she meets Will, an impossibly charming teen who has the same illness.