Emma Swan is riddled with guilt after she is tricked into kill her true love, Killian Jones. After grieving in their home for weeks, she finally decides that she isn't going to let him go that easy. After confronting the once again dark one, Rumplestiltskin, she convinces him to help her go to the underworld in a quest to find Killian, but the underworld had its own rules and getting him back will be harder than ever expected...