In his previous life, Ethan married Ava, but her rare genetic disease left him helpless — she died in a car crash. Reborn back to age eighteen as a high school senior, he swears to win her over again, and to start a business early and develop a new drug to save her. He grows a high school online shop into "Reignite Capital," attends Boston University with Ava where they fall in love, founds Ryan Pharmaceuticals, takes on the antagonists, and drives clinical trials forward — finally curing Ava and proposing to her successfully under the stars.