Caleb Prior has always been popular. Tris Prior, his little sister, is the one hidden in a crowd. She has lung cancer, and works in the family's pet store. Caleb, along with his friends always make fun of her. Four, Caleb's best friend, gets in trouble a lot, and soon, is made by his dad to volunteer at the pet store. Tris tries to avoid people and friends because she doesn't want to hurt anyone. Four wants in, but will she let him. Soon, Caleb realizes how bad the cancer is and starts helping to support his little sister. Join Tris as she keeps asking for one wish, 'Stay Alive.'