When he finds himself under attack by the Kenwadan, a gang of masked men, a politician, Mr Takamori, throws the key to his safe into an alleyway. Unexpectedly, the key is promptly picked up by a dog, who then escapes with it into a river, despite the gang's frantic pursuit. While praying at the shrine for better luck at dice, Sanosuke comes across the dog, now half-dead, and carries it back to the Kamiya dojo to be looked at by Megumi. Cue comic adventures as the dog, which Sanosuke names Notaro, promptly tears the Kenshin Group's lives apart, eating their food, stealing and burying their possessions, and generally making a nuisance of himself. But it doesn't take the Kenwadan Gang long to track Notaro down. Will Kenshin and the others be able to fend them off and find the key before the gang do?