Fans of this Emmy-winning family drama – and they are legion – get an unexpected gift as NBC opens Season 5 of the hit series two weeks earlier than the network originally planned. As the action resumes with the timeline-shifting stories, expect more focus on mom Rebecca's (Mandy Moore) troubling memory problems, as the character decides to participate in a clinical trial for a potential treatment. Obviously, it's a high-stakes issue for all three of her adult children (Sterling K. Brown, Chrissy Metz, Justin Hartley).