Happongi Hills is high-class residential area where everyone envies the owners. Inuyama family, who manages an IT company, moved Happoingi Hills from local area with their toy poodle pet, Tetsunoshin. However, Tesunoshin was shocked to know that they were very hard up. To protect their life, Tetsunoshin struggles to earn money with his friends.

　　刚由日本九州搬进东京高级住宅区“八本木山”的犬山家，在搬家后随即出现财政困难，这情况亦蔓延到犬山家所经营的企业。由犬山家独生女犬山留美所饲养的狗－彻之进，为了主人留美和犬山家的生计而出一分力，并得到秘密组织“犬乐园”的朋友帮助。但另一方面，居于白金区的里奥及其手下用尽千方百计对付他们，除了令彻之进失去身边的犬乐园朋友外，亦令犬乐园险遭崩溃……