Kawa no Hikari
is a 2007 Japanese children's adventure novel written by Hisaki Matsuura and featuring illustrations by Kazuko Shimazu. It was originally serialized in the newspaper Yomiuri Shimbun between July 25, 2006 and April 23, 2007, before being released in bound format by publisher Chuokoron-Shinsha exactly one year after its periodical debut. The book was later adapted into an animated TV special by Studio Gallop, which aired on NHK General TV on June 20, 2009 as part of the network's "Save the Future" lineup, along with other environmentally-conscious programming. The story takes place in modern Japan, and centers on a group of three rats, a father and two young sons, who must find their way back to their river home after being displaced by human construction workers. Synopsis A family of three rats, brothers Tata and Chichi, and their father, referred to only as "Dad", live in a tree trunk beside a river just outside Tokyo, just as their ancestors had for generations. However, sudden construction work by humans causes their home to be blocked off, forcing them to search for a new place to live upstream. Time becomes a factor as winter is fast approaching, leading the trio to venture in and around the dangerous city, encountering allies and enemies of all shapes and sizes. Characters The story primarily focuses on a family of three black rats: : The older and more level-headed of the two brothers. He is voiced by Fumiko Orikasa in the television film. : The younger and more energetic of the two brothers. Unlike his sibling and father, he has white fur instead of brown, a potential liability for a prey species, which he must learn to deal with and accept. He is voiced by Tomoko Kaneda in the television film. : Father of the two boys whose wife died shortly after Chichi was born. Highly protective and knowledgeable, he leads the group through both wilderness and urban sprawl. He is voiced by Kōichi Yamadera in the television film. Other characters include characters of various species: : A playful female Golden Retriever who lives with her masters near the same riverbank as the rats, and rescues Chichi after he gets caught in a river current on a water bottle. She is voiced by Aya Hirano in the television film. : A kind-hearted male brown rat who lives alone in a city library. He helps Dad and his children escape a gang of his territorial kin, who he no longer wants any part of. He is voiced by Akio Ōtsuka in the television film. : A female Russian Blue cat who "only eats fish" and lives in a quiet house with an old woman. She helps nurse the rats back to health after they nearly drown in a sewer pipe, and helps Chichi take pride in his different fur color. She is voiced by Atsuko Tanaka in the television special. : A family of Eurasian tree sparrows the rats encounter in a park. They consist of a father