The human whose name is written in the Death Note shall die. After making the hardest decision ever, another serious case confronts L. There are only 23 days left and without his best partner Watari, L has to solve the case all by himself for the very first time. In the final 23 days of L's life, he takes on one final case involving a bioterrorist group that aims to wipe out much of humanity with a virus. The film follows L as he teams up with Maki Nikaido, an elementary school student whose father created the deadly virus, and a young boy who has a gift for calculations.