Mr. Vanderhof, "Grandpa," is the head of a household of unusual personalities whom we might call a "crazy family." Neither the 1936 world in turmoil nor the depression interfere with their happiness. Enter into this, the family of Tony Kirby Jr., who is in love with Martin Vanderhof's granddaughter. The planned meeting date of these remarkably opposite clans has been somehow mistaken, so the Kirbys arrive one night early to find the household at the height of doing its own thing, which includes living room ballet, snake-charming, Roman discus throwing, fireworks experimentation and the like -- ingredients of classic comedy!