It takes other people three minutes to turn into zombies. In my family, it takes a full three days. When the whole world is gripped by zombie panic, our family gains a precious grace period thanks to our unusual constitution. My mom, a medical doctorate, immediately sets up quarantine and observation, while my dad, a veteran, quietly reinforces every door and window. We use these 72 golden hours to cram survival knowledge and stockpile supplies. On the morning of the fourth day, the five of us stand by the window: outside, the world is falling into chaos; inside, our doomsday survival class has just begun.