本季将揭开全新篇章，“如今是改变和挑战、希望和恐惧、知识和无知并存的时代。”罗西南特的船员们接到任务：探索星环之门外的新世界。
一位单亲母亲，带着一儿一女(“汤姆·里德尔”弗兰克·迪兰和艾丽西亚·戴伯南·凯瑞饰)，联手男主肖恩(克利夫·柯蒂斯饰)一起末日求生。剧集故事发生的时间与《行尸走肉》第一季相同，不过故事发生地在洛杉矶。
The fifth-year residents return for the first day of a year that will make or break their careers: Meredith faces the consequences of tampering with Derek's clinical trial and is terminated at the hospital; April tries to step up to the plate as Chief Resident in the wake of a giant sinkhole in the middle of Seattle; and Cristina and Owen are still at odds over their drasticall...
第三季以泰国一家高级度假村为背景，讲述了不同客人和员工在一周时间里的种种经历。
