''A Letter to Momo'' is an anime film that debuted at the 2011 Toronto International Film Festival, and has also been shown at other film festivals in various cities worldwide, including Honolulu (USA), Glasgow (UK), Sitges (Spain), Warsaw (Poland), and Busan (S. Korea). Director Hiroyuki Okiura was previously responsible for ''Anime/JinRohTheWolfBrigade'', but as this film was ''not'' scripted by Mamoru Oshii, it is much easier to understand.

Momo is a 11-year old girl who has recently moved to her mother's hometown on a small island in Japan's Inland Sea. She and her mother are in mourning after an accident that killed her father, whose last words to her were the words "Dear Momo," the beginning of a letter he was not able to finish. Soon after she moves in, she realises she is being followed by ''youkai''; previous gods sent to Earth to watch over the living in order to atone for their crimes.

!!This show provides examples of:

* TheAtoner: All the youkai are on earth as punishment because they broke rules as gods.
* BigEater
* BigHeroicRun
* BigThinShortTrio: Big Iwa, Thin Kawa, and Short Mame
* [[spoiler: ButNowIMustGo]]
* CloudCuckoolander / TheDitz: Mame's not all there. Umi, too, if her big brother is to be believed.
* ComicTrio
* ComingOfAgeStory
* DaydreamBeliever: Iwa and Kawa spin a tale to Momo about being trapped in a book for thousands of years, and now she's awakened them. Mame ends up believing it too because he forgot his own past.
* {{Fartillery}}: One of Kawa's attempts at trying to stop a boar from saving its children that he is about to eat.
* DisappearedDad: Momo's father's death is what kicks off the whole plot.
* DrivingQuestion: What was supposed to be on that letter?
* JerkAss: Kawa
* KidWithTheLeash: Momo, once she get ahold the pass.
* InvisibleToNormals: The Youkai are only visible to Momo because they hit her when they fell from the sky. Umi sees them, too, but it's not explained why.
* PosthumousCharacter: Momo's father.
* ShrinkingViolet: Momo, at first.
* StepfordSmiler: Momo's mother keeps everything bottled up.
* UrbanFantasy
* {{Youkai}}
* YouCanSeeMe: The youkai get the shock of their lives when they realise Momo is ''staring right at them''.