When Elliot, a brash 23-year-old living carefree in New York City, meets the sensible Mia and receives a damning diagnosis all in the same week, his world is turned completely upside down. But as their love blossoms amidst the chaos of his treatment, they discover that Elliot's illness is not the real test of their relationship – it's everything else.

Mark and Mary's meet-cute happens at a neighborhood drug store, where she is busy buying a pregnancy test, and he has to make an effort to remind her they met in college. After asking her out, he accompanies her as she takes the test, and upon it showing negative, she agrees to a date. One year later, they have fallen deeply, passionately, head over heels in love, and their whirlwind romance leads to marriage. So when Mary suddenly requests they open their relationship to “ethical non-monogamy”, Mark is taken by surprise, but agrees to try it. And that's where this story really begins.

A terminally ill man and his teenage daughter embark on a road trip from California to New Orleans for his 20th college reunion. While there, he secretly hopes she can reunite with the mother who left them long ago.