The film was "rediscovered" in the early 1970s and gained new life as an unintentional satire among advocates of cannabis policy reform. Critics, however, have panned it as one of the worst films ever made. Today, it is in the public domain in the United States.
Mae Coleman and Jack Perry are an unmarried couple living together and selling marijuana. Mae prefers to sell marijuana to customers her own age, whereas the unscrupulous Jack sells it to teenagers. Ralph Wiley, a psychotic ex-college student turned fellow dealer and Blanche help Jack sell cannabis to students. Young students Bill Harper and Jimmy Lane are invited to Mae and Jack's apartment by Blanche and Ralph. Jimmy takes Bill to the party. There, Jack runs out of reefer. Jimmy, who has a car, drives him to pick up some more. Arriving at Jack's boss' "headquarters," he gets out and Jimmy asks him for a cigarette. Jack gives him a joint. Later, when Jack comes back down and gets into the car, Jimmy drives off dangerously, along the way running over a pedestrian with his car. A few days later, Jack tells Jimmy that the pedestrian died of his injuries. Jack agrees to keep Jimmy's name out of the case, providing he agrees to "forget he was ever in Mae's apartment". Jimmy does indeed escape the consequences of his crime—a rare occurrence in the film.
Bill begins an affair with Blanche. Mary, Jimmy's sister and Bill's girlfriend, goes to Mae's apartment looking for Jimmy and accepts a joint from Ralph, thinking it to be a normal cigarette. When she refuses Ralph's advances, he tries to rape her. Bill comes out of the bedroom after having sex with Blanche and hallucinates that Mary strips for Ralph. He attacks Ralph. As the two are fighting, Jack tries to break it up by hitting Bill with the butt of his gun. The gun goes off and Mary is fatally shot. Jack puts the gun in the hand of an unconscious Bill and wakes him up. Bill sees the gun in his hand and is led to believe that he has killed Mary. The group of dealers lies low for a while in Blanche's apartment while Bill's trial takes place. Ralph loses his mind and wants to tell the police who is actually responsible for Mary's death. The film attributes Ralph's insanity to marijuana use.
Seeking advice from his boss, Jack is told to shoot Ralph so he keeps his mouth shut. Meanwhile, at the apartment, Blanche offers to play some piano music for Ralph to keep his mind off things. They are both very high and Ralph tells her to play faster. She increases her playing speed to a cartoon-like speed in one of the film's most famous and over-the-top sequences. Jack shows up and Ralph immediately senses that Jack wants to kill him so he beats Jack to death. The police arrest Ralph, Mae and Blanche. Mae talks and the gang is rounded up. Blanche explains that Bill was innocent and he is released. Blanche is then held as a material witness for the case against Ralph but, rather than testify against him, she jumps out a window and falls to her death. Ralph is put in an asylum for the criminally insane "for the rest of his natural life".
The film's story is told in bracketing sequences at a lecture given at a PTA meeting by the high school principal, Dr. Alfred Carroll. At the end of the film, he tells the parents he has been talking to that events similar to those he has described are likely to happen again and then points to random parents in the audience and warns that "the next tragedy may be that of your daughter ... or your son ... or yours or yours ..." before pointing straight at the camera and saying emphatically "... or YOURS!" as the words "TELL YOUR CHILDREN" appear on the screen.
In 1936 or 1938, Tell Your Children was financed and made by a church group and intended to be shown to parents as a morality tale attempting to teach them about the dangers of cannabis use. It was originally produced by George Hirliman; however sometime after the film was made, it was purchased by exploitation filmmaker Dwain Esper, who inserted salacious shots. In 1938 or 1939, Esper began distributing it on the exploitation circuit where it was originally released in at least four territories, each with their own title for the film: the first territory to screen it was the South, where it went by Tell Your Children (1938 or 1939). West of Denver, Colorado, the film was generally known as Doped Youth (1940). In New England, it was known as Reefer Madness (1940 or 1947), while in the Pennsylvania/West Virginia territory it was called The Burning Question (1940). The film was then screened all over the country during the 1940s under these various titles and Albert Dezel of Detroit eventually bought all rights in 1951 for use in roadshow screenings throughout the 1950s.
Such education-exploitation films were common in the years following adoption of the stricter version of the Production Code in 1934. Other films included Esper's own earlier Marihuana (1936) and Elmer Clifton's Assassin of Youth (1937) and the subject of cannabis was particularly popular in the hysteria surrounding Anslinger's 1937 Marihuana Tax Act.
The concept of after-market films in film distribution had not yet been developed, especially for films that existed outside the confines of the studio system, and were therefore considered "forbidden fruit." For this reason, neither Esper nor original producer George Hirliman bothered to protect the film's copyright; it thus had an improper copyright notice invalidating the copyright. Over 30 years later, in the spring of 1972, the founder of NORML, Keith Stroup, found a copy of the film in the Library of Congress archives and bought a print for $297. As part of a fundraising campaign, NORML showed Reefer Madness on college campuses up and down California, asking a $1 donation for admission and raising $16,000 toward support for the California Marijuana Initiative, a political group that sought to legalize marijuana in the 1972 fall elections. Robert Shaye of New Line Cinema eventually heard about the underground hit and went to see it at the Bleecker Street Cinema. He noticed the film carried an improper copyright notice and realized it was in the public domain. Seeking material for New Line's college circuit, he was able to obtain an original copy from a collector and began distributing the film nationally, "making a small fortune for New Line."
Reefer Madness is considered to be a cult classic and one of the best examples of a midnight movie. Its fans enjoy the film for the same unintentionally campy production values that made it a hit in the 1970s.
The Los Angeles Times has claimed that Reefer Madness was the first film that a generation embraced as "the worst." Leonard Maltin has called it "the granddaddy of all 'Worst' movies." Las Vegas CityLife named it the "worst ever" runner-up to Plan 9 from Outer Space, and AMC described it as "one of the worst movies ever made." The film received mixed reviews from critics and holds a 46% rotten rating on Rotten Tomatoes.
Sean Abley's stage adaptation, Reefer Madness, ran for a year in Chicago in 1992.
The film was spoofed in a musical of the same name, which was later made into a made-for-television film in 2005, which featured actors such as Alan Cumming, Kristen Bell, Christian Campbell and Ana Gasteyer.
In 2004, 20th Century Fox, in collaboration with Legend Films, released a colorized version of the film on DVD. The original release date was April 20, 2004, a reference to the drug slang term "420". Also during the film, the number "4" and then "20" is flashed very quickly (as a joke on subliminal messages), which is an effect added by Legend Films. The color version features intentionally unrealistic color schemes that add to the film's unintentionally campy humor. The smoke from the "marihuana" was made to appear green, blue, orange and purple, each person's colored smoke representing their mood and the different "levels of 'addiction'". The DVD also included a short film called Grandpa's Marijuana Handbook; a new trailer for Reefer Madness produced by Legend Films; and two audio commentaries: one discussing the color design and the other being a comedic commentary by Michael J. Nelson, formerly of Mystery Science Theater 3000 fame. Legend owns the copyright to the colorized version of Reefer Madness. While most have praised the new color version for its campy treatment of the cult film, some viewers claimed that the color choices would better suit a film about LSD than a film about cannabis. A DivX file of the colorized version with the commentary embedded is available as part of Nelson's RiffTrax On Demand service. In 2009, a newly recorded commentary by Nelson, Kevin Murphy and Bill Corbett, called the "Three Riffer Edition", was released by RiffTrax, and was the feature of a RiffTrax live event on August 19, 2010.