16-year-old teenager Leaf runs away from home, skipping classes and ending up in a peculiar place called City of Lost Things. There he meets Baggy, a 30-year-old plastic bag. Baggy never sees himself as just another piece of junk. He has a purpose in his life – to lead his tribe to flee City of Lost Things. But he needs the help from Leaf to fight the dreadful army of the Armors.