A fitting end.
While this movie completely goes against the established Death Note lore, Manga or Anime, it serves it's purpose well as the close to a trilogy of live action films. L finds himself with 23 days left to live after writing his own name in the Death Note in anticipation of Light Yagami's actions, and now even though Kira is dead, and L has given his own life to stop the man who thought himself god, L is trying to solve as many crimes as possible in his final days on Earth, and despite Ryuk's attempts to tempt L into using the Death Notes, L burns the two books so no human will ever be able to use them again, thus sending Ryuk back to the Shinigami realm and putting an end to the nightmare that was Kira once and for all. But when some who are as smart as L himself release a virus that may doom humanity to extinction, will L regret destroying the notebooks as he races to stop a group whose names he knows, but whose actions are difficult to predict?
Though not true to established Death Note mythology, this film was an excellent close to the live action trilogy. One problem I always had with L was, even though he was the true hero of Death Note, I cared more about Light, and thankfully this movie made me really care about L. It was nice to see Near make a live action appearance as the mute boy who is immune to the deadly virus described as a cross between the Flu and Ebola.
Fact is this was well written and fun to watch, if you liked the first two Death Note films you'll enjoy it a lot. If you didn't like Death Note and Death Note 2 the Last Name then you have already sold your soul to the Shinigami, and should skip this film I can only describe as Outbreak meets Death Note.