这对双胞胎狗非常快乐，和主人一起住在家里，想做什么就做什么。当它们不为谁是老大而争论不休的时候，它们喜欢带着家人出去散步，早上喝牛奶，玩抛接球游戏，只要喜欢，就会养宠物。突然间，一切都变了。早上没有牛奶，陌生人带着他们去散步，也没有跑步和抛接球游戏，这到底是怎么回事？看来家里来了个新成员——他们必须马上阻止这一切，所以他们想出了一个计划.......

The twin dogs are very happy, living in their house with their owners and getting up to anything they want. When they aren't arguing over which of them is the oldest, they like to take their family out for walks, drink milk in the mornings, play catch and get pet whenever they fancy. All of a sudden, everything changed. No milk in the mornings, strangers are taking them for walks and there's no running or playing catch - what on earth is going on? It appears there's a new member of the household - they must put a stop to this immediately, so they come up with a plan . . .