In the 1940s in the small town of Jupiter Hollow, two sets of identical twins are born in the same hospital on the same night. One set to a poor local family and the other to a rich family just passing through. The dizzy nurse on duty accidentally mixes the twins unbeknown to the parents. Our story flashes forward to the 1980s where the mismatched sets of twins are about to cross paths.
'Toon star Roger is worried that his wife Jessica is playing pattycake with someone else, so the studio hires detective Eddie Valiant to snoop on her. But the stakes are quickly raised when Marvin Acme is found dead and Roger is the prime suspect.
After being discharged from the Army, Brian Flanagan moves back to Queens and takes a job in a bar run by Doug Coughlin, who teaches Brian the fine art of bar-tending. Brian quickly becomes a patron favorite with his flashy drink-mixing style, and Brian adopts his mentor's cynical philosophy on life and goes for the money.
When plans with her boyfriend fall through, high school senior Chris Parker ends up babysitting the Anderson kids, Brad and Sara. What should be a quiet night in, however, turns into a series of ridiculous exploits, starting when they leave the house to pick up Chris' friend Brenda. Soon, Brad's buddy Daryl is involved, and the group must contend with car thieves, blues musicians and much more.