A renowned linguistics professor at Columbia University, Alice Howland, finds her life beginning to unravel as she starts to forget words and gets lost on her routine jog on campus. Her successful career and happy family life, shared with her husband and their three grown children, are put to the test when, after her 50th birthday, she receives a devastating diagnosis of early-onset Alzheimer's disease. Alice's struggle with the rapidly progressing illness is compounded by the pressures and expectations of her high-achieving family, raising questions about her professional identity and future.

As Alice grapples with her diminishing mental acuity, she endeavors to maintain her independence and sense of self. She develops coping strategies and records a video message to her future self, setting out a plan for when her condition worsens. At the same time, her relationships with her family come into focus, especially with her youngest daughter, who is an aspiring actress and to whom Alice had previously been closest in temperament and interests. The inexorable progression of Alice's disease challenges each family member differently, testing the bonds that hold them together as they navigate the unpredictable and heart-wrenching terrain of her decline.