Booked for a weekend stint in Detroit, the Partridge Family and manager Reuben Kincaid get quite a surprise when they see the club where they are supposed to perform. Called "The Fire House," the club is just that – an old fire house in the ghetto. Owners Sam and A.E. Simon started the club as an inexpensive place of entertainment for the people living in the black neighborhood... but they're in debt to a loan shark named Heavy, who can't wait to take the club away from them and will use any gangster-tactic in the book to do it. When Shirley learns that The Temptations were supposed to appear at the "Fire House" – and not the family – and after discussing it with the Simons, it's apparent that Heavy deliberately had the bookings mixed up so that Sam and A.E. wouldn't be able to make their last payment. In an effort to help, Shirley and the kids give a free performance, but Heavy and his boys see to it that there is no audience.
The next day, A.E. and Sam are without hope. Then Shirley comes up with the idea of having a block party and asking for donations to save the club. Sam gets the local business men to donate refreshments... Shirley takes care of the legal permits... even Reuben pitches in by getting the disc jockeys to announce the event... and Danny charms a group of rough-looking karate experts known as the Afro-American Cultural Society, into getting an orchestra together. The block party is a complete success and the donations give the Simon brothers more than enough money to take care of Heavy.