Despite the similarity of their surnames, author H.G. Wells is no relation to dramatist and film-maker Orson Welles, who went on to even greater fame (or notoriety) by directing Citizen Kane.
The drama was part of CBS's Mercury Theater on the air series. The radio play was a contemporary retelling of the events of the novel, presented as a series of news bulletins in documentary style. Welles played recordings of the radio reports of the Hindenburg disaster to the cast to demonstrate the mood he wanted. The invasion was relocated to Grover's Mill, New Jersey and set in the present time. The play started as an ordinary music program, interrupted by news flashes. The news reports grew more frequent and increasingly ominous, ending with a lone reporter talking from the top of a building, above the poison gas, asking if there was anyone out there.
Many people missed or ignored the announcements before the program and shortly before the start of the second half, that the program was a fictional play. In the atmosphere of growing tension and anxiety in the days leading up to World War II, panic ensued, with people thinking they could smell the poison gas or see the flashes of the fighting in the distance. A study by the Radio Project discovered that most of the people who panicked did not think that it was an invasion by Martians, but by the Germans. Other studies have suggested that the panic was exaggerated by the media, but it remains clear that many people were fooled. When a meeting between H.G. Wells and Orson Welles was broadcast on Radio KTSA San Antonio on October 28 1940 the former expressed a lack of understanding of the apparent panic and suggested that it was, perhaps, only pretence put on, like the American version of Halloween, for fun. The two men and their radio interviewer joked politely about the matter, though clearly with some embarrassment.
The drama has been rewritten to apply to other locations and rebroadcast, with similar results. In 1944, a broadcast in Santiago, Chile resulted in panic, including the mobilization of troops by the governor. In 1949, in Quito, Ecuador, a broadcast panicked tens of thousands. Listeners who were enraged at the deception set fire to the radio station, killing fifteen people.
The episode is briefly referred to in Radio Days by Woody Allen. The Los Angeles CBS affiliate radio station, KNX (1070 AM), re-broadcasts the radio program every year on Halloween. Other radio stations around the world have also repeated the broadcast, and it has been released several times on LP, tape and CD, sometimes accompanied by other Welles dramatizations.
A 1975 television film for ABC, The Night that Panicked America, dramatizes the public's panicked reaction to the broadcast, but comes across as a fairly standard disaster movie (albeit one in which the disaster is assumed rather than actual). Its best scenes are those which take place in the radio studio itself, as they give a taste of the atmosphere of live radio production.
Because of the panic caused in the 30's and 40's by this radio play, TV networks have deemed it necessary to post bulletins to their viewing audience to inform them some TV stories are fictional drama, and not really happening. Disclaimers of this sort were shown during broadcasts of the 1983 television movie Special Bulletin. One network placed disclaimers in an October 1999 TV movie dramatizing the possible disastrous effects of the Y2K bug even though it was obviously drama and was unlikely to be confused with reality.
See also: false document, hoax