Bicycle (Jitensha) is the story of Mamoru Amagaya, a young man struggling to find meaning in life.
A co-worker confronts Mamoru on his apparent apathy toward life, and this results in Mamoru leaving his job out of humiliation. Now alone and without work, just as it seems that things could not possibly get worse, parts of Mamoru's bicycle begin to disappear, one by one. In frustration, Mamoru leaves a note for the thief, begging him to just take the whole thing. The note left in response is signed God, leaving Mamoru only more confused. At last, when the only remaining piece of the bicycle is a lonely bell, Mamoru receives an envelope, containing addresses at which each piece of the bicycle might be retrieved.
Puzzled yet intrigued, Mamoru embarks on a journey to resurrect and reassemble his beloved possession. As he seeks out each piece of the missing whole, Mamoru begins to discover that he himself is in a healing process. As he puts his bike together piece by piece, he realizes that he himself is in the process of being reassembled in the same way, by one far greater than himself.