From the late teens through the late 1950s classical exploitation films operated in the shadow of the classical Hollywood cinema. The men that made and distributed exploitation films were sometimes called "the Forty Thieves," and several came from carnival backgrounds. Some companies were fly-by-night outfits that produced a film or two and then disappeared. However, many individuals and companies were around for years: Samuel Cummins (1895–1967) operated as Public Welfare Pictures and Jewel Productions; Dwain Esper (1892–1982) used the Road Show Attractions name; J. D. Kendis (1886–1957) made films under the Continental and Jay Dee Kay banners; Willis Kent's (1878–1966) companies included Real Life Dramas and True Life Photoplays; and Louis Sonney's Sonney Amusement Enterprises dominated West Coast distribution.
Exploitation movies were invariably low budget—usually made for far less than the average B movie. Most exploitation films were made for under $25,000 and some for as little as $5,000. Shooting schedules were less than a week, with some films being shot in as little as two or three days. (Unlike B movies, which were used to fill out the bottom half of a double feature, exploitation films were often expected to stand on their own.) Their low budgets and accelerated shooting schedules meant that exploitation films featured stilted performances, poor photography, confusing plots, and startling gaps in continuity. On almost every level they were bad films. Many of these movies have a delirious quality, shifting between long passages of expository dialogue and confusing action. But what they lacked in narrative coherence they made up for by offering audiences moments of spectacle that could not be found in mainstream movies. That spectacle might come in the shape of scenes in a nudist camp, footage of childbirth or the effects of venereal diseases, prostitutes lounging around in their underwear, or women performing striptease dances. These scenes of spectacle often brought the creaky narrative to a grinding halt, allowing the viewers to drink in the forbidden sights. As a result of such scenes exploitation movies were always advertised for "adults only."
In addition to the forbidden sights on the screen, exhibitors were often provided with elaborate, garish lobby displays. Sex hygiene films could be accompanied by wax casts showing the process of gestation and birth or the effects of VD. Drug movies came with displays of drug paraphernalia. In many instances the films were accompanied by lectures, which were little more than excuses to pitch books on the subject of the film. For a dollar or two the audience could buy booklets with titles like "The Digest of Hygiene for Mother and Daughter." Pitchbooks provided an additional source of income to the distributor.
A small core of urban skid row grindhouses played exploitation films constantly. But the best market for these films consisted of regular theaters, in cities or small towns, that periodically took a break from Hollywood product to play a racy—and profitable—exploitation movie. The movies cloaked their suggestive stories and images in the mantle of education. Almost all exploitation films began with a square-up—a brief prefatory statement that explained the necessity of showing a particular evil in order to educate the public about it. Given the difficulty of getting information on such issues as childbirth and birth control, some of the movies did have a legitimate educational component. But they were produced primarily to make a buck. Exploitation movies were often available in "hot" and "cold" versions to accommodate local censorship or taste, and to extend the potential of pocketing that buck. And if audiences did not get the spectacle that they had been led to believe they would see from the lurid advertising, a roadshowman could always throw on a "square-up reel" of nudist camp footage or a striptease dance to sate the crowd.
Because only a handful of prints of any film circulated around the country at any one time, many classical exploitation films were in release for decades. It was a common practice to re-title a film to extend its life on the road; some movies were known by as many as five or six titles over time. Among the perennial hits on the exploitation circuit were sex hygiene movies such as The Road to Ruin (1934) and Damaged Goods (1937); drug movies like Marihuana (1936), The Pace That Kills (1935), and She Shoulda Said No (1949); vice films such as Gambling with Souls (1936) and Slaves in Bondage (1937); nudist movies like Elysia, the Valley of the Nude (1933) and The Unashamed (1938); and exotic movies (often featuring nearly naked natives) such as Virgins of Bali (1932) or Jaws of the Jungle (1936).
The most successful exploitation film of the classical era was Mom and Dad (1944). Producer Kroger Babb (1906–1980) had toured with earlier sex hygiene films and in 1944 decided to make a more up-to-date film. The story of a high school girl who discovers that she is "in trouble," Mom and Dad included films within it that showed childbirth, a Caesarian operation, and venereal diseases and their treatment. Babb sold the film aggressively and at one point after World War II he had more than twenty units on the road with the film, each with its own "Elliott Forbes," an "eminent hygiene commentator" who provided the lecture and book pitch. Millions of men, women, and teenagers saw Mom and Dad and it soon had competition from several direct imitations: The Story of Bob and Sally (1948), Because of Eve (1948), and Street Corner (1948). Eventually the owners of the four films joined together in a consortium to distribute the movies in a way that minimized direct conflict. Mom and Dad was still playing drive-in dates into the 1970s and some estimates have placed its total gross over the years at $100 million. But as the 1950s progressed, the Production Code was relaxed and many of the old topics that had been grist for exploitation movies—drug use, unwed motherhood—were folded back into the list of acceptable subjects for Hollywood films.