WXIII: Patlabor the Movie 3

Also known as Wasted 13, WXIII: Patlabor The Movie 3 is an unrelated side story taking place somewhere between the first and second movies. It barely features the main cast of Patlabor, thought labors themselves are still visible in the setting and related to the plot.

The film follows detectives Hata and Kusumi who are investigating a strange chain of labor vandalism. They seem random at first, but eventually the detectives figure out the pattern along with other things that only end up making the situation more complicated. Namely a gigantic fish monster that later is revealed to be called "prototype 13". While on the case, Hata meets a female university professor called Saeko Misaki and develops feelings for her. Unfortunately, there's more to her than meets the eye and as the film goes on their relationship takes a turn for the worse.

The last and darkest of the three movies, Patlabor The Movie 3 falls heavily to the serious side of the Sliding Scale of Silliness Versus Seriousness. While Mamoru Oshii was only the producer instead of direcetly working on the film, it is much like Jin Roh and Ghost In The Shell Innocence that he made around the same time, both being very moody and grim.

The DVD release includes three Mini Pato shorts which are hilarious ~30 minute animations done with paper cutouts on sticks that go into detail about things like Ohta's oversized revolver and its anti-labor ammunition.

Tropes used in WXIII: Patlabor the Movie 3 include:

Asteroids Monster: While escaping prototype 13 at the construction site, one of the cops triggers several emergency doors to trap it or hopefully even kill it. Part of the monster's tail gets stuck under the door and is cut off entirely. It's later recovered and hauled off for biological inspection where it apparently rapidly mutated into a miniature version of the original body and killed the scientists examining it.
Bittersweet Ending: Misaki committs suicide in front of Kusumi, as the monster made from her daughter's mutated cancer cells is obliterated by the Self Defence Forces.
Cosmic Horror: The monster's seafood platter looks are decidedly lovecraftian & its origins in Mysterious Antarctica are rather evocative of At the Mountains of Madness.
Creating Life: Using mutated cancer cells.
Dark and Troubled Past: Saeko Misaki, definitely.
Darkness Equals Death: Hata and Kusumi notice a construction site with no lights on while driving back from a crime scene and go investigate. Prototype 13 had eaten all the workers and ends up eating the cops that were driving the car, while Hata and Kusumi barely make it out alive.
Eyeless Face: Prototype 13.
Failure Is the Only Option: Hata wants to save Misaki from herself, but considering her backstory and what she did it becomes clear that Hata was doomed to fail.
Gone Horribly Wrong: Possibly subverted. The fish-like monster, the titular prototype 13 is initially dumped into Tokyo Bay because Misaki's employers thought it was programmed to die after a certain amount of time and they wanted to dispose of the remains in secret. Misaki never programmed it to die, and the monster grew in freedom like she wanted to. This ended up being a really bad thing for everyone BUT Misaki.
Gray Rain of Depression: The tragic conclusion at the dome.
Hybrid Monster: Prototype 13 is ambiguously lobster-like, has glowing lights on tendrils like an anglerfish and was injected with human cancer cells
Ill Girl: Misaki's daughter died from cancer.
Imported Alien Phlebotinum: The monster was partly created from alien cells found in Antarctica.
Jade-Colored Glasses: Hata's character developement seems to ultimately lead to this during the course of the film. His partner has a different, more cynical although realistic world view, and Hata's potential love interest is revealed to be broken on the inside to the point where she created a monster she considers her daughter and kills herself when it is destroyed before her.
Kaiju
Mutant: Prototype 13.
Odd Couple: Detective Hata is young, plays baseball and is often letting his emotions affect his police work. Detective Kusumi is middle-aged and snarky, preferring not to rush things or let his emotions get in the way of work.
Replacement Goldfish: Misaki created the 13th prototype from her daughter's mutated cancer cells, and saw it as her daughter being revived. It gets pretty disturbing when the monster occasionally screams with a human voice instead of generic roars, and just before it dies is revealed to have human breasts.
Sliding Scale of Silliness Versus Seriousness: Just compare this to the series, or even the first movie.^[context?]
Soundtrack Dissonance: Beethoven's Pathetique is playing while the Japanese Self Defence Forces burn a genetically mutated fish monster to death.
Take My Hand: Poor, poor Misaki.
Twisted Ankle: Kusumi has to wear an elbow crutch because of an accident he had just prior to the events of the film. He almost gets eaten by a giant monster because of it.