As summer blockbuster Edge of Tomorrow hits theaters in Europe this week and America next week, now is the perfect time to look at the Japanese novel it is based on: the futuristic time-loop war story All You Need is Kill.

Good – A Well Thought-out Time Loop


The setup of All You Need is Kill is as follows: New recruit Keiji Kiriya has joined the exoskeleton-wearing Japanese military to fight the mimics, a frog/starfish-like alien army that has been invading the Earth for decades. However, in his first battle he is killed—only to wake up 30 hours before his own death.

Like the film Groundhog Day, All You Need is Kill is a time-loop plot—and a well thought-out one at that. Keiji does not know how or why he is repeating the same day and a quarter again and again. However, he is quick to figure out the rules and constraints of the loops (i.e., that he can carry over memories but nothing physical) and thus develops a way to use the loops to the best effect—which is to say get good enough at fighting that he isn't killed.

At first, it's all about personal self-improvement—training his mind and reflexes through practice with his veteran sergeant and learning from the experience of numerous real battles. But soon it also becomes one of materiel—i.e., the fact that no matter how good you are, guns eventually run out of ammo. Of course, melee weapons—like a giant battle axe, for example—do not. Thus Keiji must use his knowledge from countless loops to devise a way to get the equipment he needs as well as learn to master it.

Good – The Personal Pressures

The other main aspect of the story is the psychological pressure of being trapped in the time loop. Over the course of the novel, Keiji dies in many horrible ways as do those around him—sometimes it's even his fault when they do. Moreover, while he has a goal, there is no guarantee that surviving the battle will be enough to break the loop. And once he has perfected his efficiency in the loop, he lives nearly the exact same day to the second every day. He has the same conversations, eats the same food, and does the same basic prep work for the battle. Watching how this repetition and isolation affects his personality is more than a little interesting. It's also interesting to see how little changes, like a frown at the wrong time can completely derail the perfect loop.


Good – The Full Metal Bitch


But the emotional core of the story doesn't really center around Keiji, but rather humanity's greatest soldier, Rita Vrataski, the “Full Metal Bitch.” On the battlefield, she is unstoppable. She has never been injured and her small unit is responsible for the vast majority of humanity's recent victories against the mimics. She is the unreachable goal to which Keiji aspires to be through his loops. But, of course, there is much more to her than that.

[Skip to the next section to avoid spoilers.]

Like Keiji, Rita is also a time-loop veteran—though, she figured out what caused hers and how to break it. Thus, she is the one person alive able to understand Keiji's plight on both an intellectual and emotional level. To both of them, their meeting is the end to their isolation—and probably the happiest moment of Rita's life. Also, learning her backstory—how the war has affected more rural areas and what life is like for normal people—does a great job of fleshing out the setting.


Mixed – Explains a Bit Too Much

While Rita's backstory organically develops the setting, there is a section of the book that does not: the origin of the mimics. As it is information that no human could possibly know, the novel grinds to a halt mid-story to give us a history lesson where the author directly addresses the reader. While interesting, learning about how the mimics came to be is useless exposition as far as the story is concerned. There is nothing we learn in this section that affects how the story unfolds as none of the characters are aware of—nor become aware of—this information. Moreover, this explanation makes the mimics seem less of a threat once we know exactly what they are instead of their remaining a faceless, monstrous threat with unknown goals.


Bad – A Contrived Ending


[Skip to the "Final Thoughts" section to avoid spoilers.]

It is in the final battle that the story falls apart because of its contrived climax and subsequent resolution. Basically, it feels like the author wanted Keiji and Rita to fight in a tragic battle to the death and thus forced the plot to make this happen—despite the fact that it doesn't make sense in the world he has built. Don't get me wrong, you can definitely have this trope in a story and have it done well; but when the main good guys battle to the death because there is “no other way,” there sure as hell better actually be “no other way.”


Even while reading their climatic battle, I was able to easily think of two ways to possibly solve their problem without one needing to kill the other—e.g., (1) stopping one of their hearts in a controlled medical setting and then attempting to resuscitate him or her seconds later or (2) the even safer option of simply putting one of them on a plane the moment the loop starts to get them out of antenna range. And while these possible solutions may not have worked, the fact that Keiji and Rita didn't even think of and subsequently try any possible solutions at all makes our previously intelligent heroes seem like muscle-bound morons.

Moreover, Keiji is in a time loop. Even if he can't think of a solution on the spot, he has a literal eternity to find and test for a solution that doesn't involve killing Rita. However, she suddenly explains mid-battle that one of them needs to die and—so we can get our tragic ending—the two stop thinking entirely and get to fighting.


And it only gets dumber when you realize the whole point of the fight is for the stronger one of the two to continue on fighting the mimics. Unfortunately while Keiji wins, it's not because he is better at mimic killing but because he has watched Rita long enough to know her tells. Thus humanity is left weaker, not stronger.

Final Thoughts


All You Need is Kill is a great time loop story and puts a lot of thought into what it would be like to live in that situation for a prolonged period of time. Moreover, it has some great mysteries and an interesting cast of characters—especially Rita. And while the climax and ending fall apart completely if you think about them at all, it is still an enjoyable read and well worth the scant few hours it takes to read it.

All You Need is Kill was originally published in Japan in 2004. It is currently available in English under both the titles All You Need is Kill and Edge of Tomorrow.


[Note: Anime-style images in this post come from the manga.]

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