The Last Word follows Harriet Lauler, Shirley MacLaine, a retired, tightly wound, controlling businesswoman who becomes determined to have the final say in her life story. Harriet hires a young writer, played by Amanda Seyfried, to help her craft her obituary in advance. As they work together, Harriet begins to reflect on her past and reevaluate her relationships.

In her quest for redemption and a meaningful legacy, Harriet starts to connect with her new found friends in unexpected ways, including a plucky but troubled young girl named Brenda, played by AnnJewel Lee Dixon .

Through humor and heartfelt moments, the film explores themes of self-discovery, second chances, and the importance of human connection.