Almost 20 years after the start of the original "Brady Bunch" the kids are grown up and have kids of their own. Everyone is having a wonderful time back at the family house for Christmas, until Mike learns of a structural problem in one of the buildings he designed. As he is inspecting the problem, the building collapses, trapping him inside. As the whole family waits by the pile of rubble, they fear the worst. Will Dad be all right?

The slapstick adventures of hapless Gilligan, long-suffering Skipper and their gang of mismatched castaways, all stranded on an uncharted desert isle after their tiny ship hit stormy weather.

女主人卡萝失踪已久的前夫罗伊突然出现，并且想和卡萝及三个女儿再续天伦之乐，但是卡萝的现任老公麦克可不会袖手旁观，任人破坏现今美满的家庭。但问题出在这个破坏者是卡萝失踪且未离婚的合法老公，到底这个“脱线家族”要如何以他们“少根筋”的天性，来解决这个凡人难解的三角习题