The city's District Attorney is murdered, and a newspaper reporter investigates. He starts finding out that everything wasn't quite as cut and dried as it appeared to be.
Tommy McCoy and "Dude" Markey are both in love with Harlem singer/dancer Nita. Markey robs a jewelry store and turns the loot over to gang-boss Murray Howard. Later, Markey robs the safe, steals the jewelry, and, in order to get rid of his rival for Nita, frames the robbery on McCoy. The latter's big-brother thinks otherwise and, with Nita's help, sets out to prove it.
Based on the comic strip by Gene Byrnes, the "Reg'lar Fellers", and one girl-feller, tinker with building a land/water machine, form a kid-band and go on the radio, celebrate a birthday, get involved with gangsters...and reunite a wealthy recluse with her baby granddaughter and estranged daughter-in-law.
When crime boss Big Mike Morgan is killed, his lieutenant, "Doc" Rogers, learns that Morgan has a son named Edward living in the country with his mother. Rogers has naïve Edward brought to the city and installs him as the head of Acme Protective Agency. Good-hearted Eddy assumes his company provides insurance, rather than extortion-- But don't be too hard on the guy, he still doesn't know he's Baby Face Morgan, the most feared gangster in the city!
Quality was seldom a consideration in the low-budget films of PRC Studios; still, the company was a welcome harbor for character actors who aspired to occasional leading roles. In Boss of Big Town, veteran supporting player John Litel is top-billed as crusading city market official Michael Lynn. When a criminal gang muscles in on the local food distribution markets, Lynn vows to throw the rascals out. First, however, he pretends to join the villains as a paid government stooge, the better to find out the identity of the "Mister Big" behind the distribution racket. The exposure of the "mystery villain" will come as a shock to fans of the 1927 Cecil B. DeMille epic The King of Kings--but not to dyed-in-the-wool movie buffs.
Dramatic events in a Harlem apartment house center around Pa Wilkins, chosen by the Better Business League to replace their ousted, crooked leader Marshall...who wants revenge; and Pa's ward Jim Bracton, a two-timing Romeo whose affairs are coming to a crisis. And hanging around is Marshall's murderous junkie henchman, Lomax. Will it all end in someone's being killed?