在这部大熊杰克剧情片中,这部影片讲述了一位父亲如何孤身一人抚养儿子长大的故事。 这个家虽然乱作一团，但生气勃勃。约翰·利里总是充满活力，精心照顾从纽约来到北加利福尼亚的两个儿子：12岁的杰克和3岁的迪伦。每当孩子们遇到困难的时候，约翰总是把欢笑送给他们。 也许在别人眼里，约翰不是个完美的父亲，有时杰克竟然说不清谁是一家之主；但是这样的父亲懂得如何爱孩子，如何帮助孩子，又有什么可指责的呢？
Danny DeVito is John Leary, a professional clown, whose wife's death in a car accident has left him to care for his two young boys. Loving, but useless at the daily job of fathering, the onus falls on plucky Jack the Bear (Robert J. Steinmiller Jr.) Leary's conscience, and a quantity of alcohol, leads him to denounce a neo-fascist candidate on his children's TV program, and also to the kidnapping of youngest son Dylan (Miko Hughes) by a disturbed neo-Nazi supporter.
