For the average moviegoer, a "B" movie was simply any movie at all that a theater advertised in small letters as a "plus" or a "a special added attraction" to the main feature.

Generally, the special added attraction played before Interval, so that patrons would not feel cheated or too unhappy if they arrived late and missed the first ten or twenty minutes. Therefore, in the minds of many (though by no means most) moviegoers, the "B" was a movie of no special merit or entertainment value.

To a cinema manager, however, a "B" was any film at all with a running time of less than 70 (or 75) minutes. This short running time meant that the movie could not stand alone, even as a main attraction, because patrons demanded that the whole show run not less than 150 minutes in Nob Hill areas or 180 minutes in less affluent neighborhoods.

The distributor (or "film exchange"), on the other hand, applied yet another definition. To the exchange, a "B" meant any feature with an entertainment quotient so low it had to be sold to exhibitors at the lowest flat rate possible.

This book extensively covers all three of these categories. Of course, patrons did have their favorites. Mysteries were overwhelmingly popular, especially series movies like Sherlock Holmes, Charlie Chan, Edgar Wallace and Torchy Blane. Westerns and slapstick comedies were also strongly favored in blue-collar neighborhoods, as were the series pictures of Blondie and Maisie.

Mind you, it often transpired that patrons regarded the "B" feature as more entertaining than the extensively touted "A" attraction, particularly if it was actually an "A" in disguise (a film the exchange had decided to offload at bargain basement rentals). "You're in the Navy Now" (Gary Cooper), "Zaza" (Claudette Colbert), "Zero Hour!" (Dana Andrews, Linda Darnell, Sterling Hayden), "The Young Stranger" (James MacArthur, Kim Hunter), "Without Honor" (Laraine Day), "The Wistful Widow of Wagon Gap" (Abbott and Costello), “Whistling in Brooklyn" (Red Skelton), "What Next, Corporal Hargrove?" (Robert Walker), "Western Union" (Randolph Scott), "Tropic Zone" (Ronald Reagan, Rhonda Fleming), "Trooper Hook" (Joel McCrea, Barbara Stanwyck), "That Certain Woman" (Bette Davis, Henry Fonda), and "Texas Carnival" (Esther Williams, Howard Keel, Ann Miller), were just some of many films offloaded by distributors, as detailed in the book.

In many cases, the bargain price offered to cinemas reflected neither the movie’s extensive budget nor its entertainment value. With "Scaramouche" (Stewart Granger, Eleanor Parker, Janet Leigh, Mel Ferrer) for instance, it was the title itself that held no appeal to patrons or exhibitors; "Way Out West" (Laurel and Hardy) was disadvantaged by its short running time; "White Tie and Tails" (one of the best "B" movies ever made) by the studio’s decision to cast perennial heavy Dan Duryea as the hero. "Romance in Manhattan", a Ginger Rogers vehicle, was also saddled with an unpopular male lead (Francis Lederer); and those little gems, "Death on the Diamond" (Robert Young), "Kind Lady" (Ethel Barrymore), and "Kid Glove Killer" (Van Heflin, Marsha Hunt) were simply undone by the mere fact that they were products of MGM's "B" unit.