Radio drama (or audio fiction, audio drama, audio play, radio play,LC subject heading. radio theatre, or audio theatre) is a dramatised, purely acoustic performance. With no visual component, radio drama depends on dialogue, music and sound effects to help the listener imagine the characters and story: "It is auditory in the physical dimension but equally powerful as a visual force in the psychological dimension."Tim Crook: Radio drama. Theory and practice. London; New York: Routledge, 1999, p. 8. Radio drama includes plays specifically written for radio, docudrama, dramatised works of fiction, as well as plays originally written for the theatre, including musical theatre, and opera.

Radio drama achieved widespread popularity within a decade of its initial development in the 1920s. By the 1940s, it was a leading international popular entertainment format. With the advent of television in the 1950s, radio drama began losing its audience. However, it remains popular in much of the world.

Recordings of OTR (old-time radio) survive today in the audio archives of collectors, libraries and museums, as well as several online sites such as the Internet Archive.

By the 21st century, radio drama had a minimal presence on terrestrial radio in the United States, with much American radio drama being restricted to rebroadcasts of programmes from previous decades. However, other nations still have thriving traditions of radio drama. In the United Kingdom, for example, the BBC produces and broadcasts hundreds of new radio plays each year on Radio 3, Radio 4, and Radio 4 Extra. Like the US, Australia's network the ABC has abandoned broadcasting drama but in New Zealand on RNZ, continues to promote and broadcast a variety of drama over its airwaves.

Thanks to advances in digital recording and Internet distribution, radio drama experienced a revival around 2010. Podcasting offered the means of inexpensively creating new radio dramas, in addition to the distribution of vintage programs.

The terms audio dramaCompare the entry to Hörspiel e.g. in: dict.cc – Deutsch-Englisch-Wörterbuch or audio theatre are sometimes used synonymously with radio drama; however, audio drama or audio theatre may not necessarily be intended specifically for broadcast on radio. Audio drama can also be found on CDs, cassette tapes, podcasts, webcasts, or other digital downloads as well as broadcast radio.

History The Roman playwright Seneca has claim as a forerunner of radio drama because "his plays were performed by readers as sound plays, not by actors as stage plays... In this respect Seneca had no significant successors until 20th-century technology made possible the widespread dissemination of sound plays."Martin Banham (ed.). The Cambridge Guide to Theatre. Cambridge, NY: Cambridge University Press, 1995, "Radio drama", p. 896.

1880–1930: early years English-language radio drama seems to have started in the United States.Historian Alan Beck reports in The Invisible Play: B.B.C. Radio Drama 1922–1928 that "The first English experiment in radio drama" took place October 17, 1922, in Great Britain. But U.S. stations were broadcasting drama prior to this. See following. A Rural Line on Education, a brief sketch specifically written for radio, aired on Pittsburgh's KDKA in 1921, according to historian Bill Jaker.Bill Jaker, March 27, 1998, email post to the OTR Digest Newspaper accounts of the era report on a number of other drama experiments by America's commercial radio stations: KYW broadcast a season of complete operas from Chicago starting in November 1921."Opera carries 1,500 miles by radio phones", November 12, 1921 Chicago Tribune; "Radi-Opera" November 17, 1921 Chicago Tribune In February 1922, entire Broadway musical comedies with the original casts aired from WJZ's Newark studios."Two plays by wireless", February 4, 1922, New York Times; "Million to hear musical comedy", February 12, 1922 Los Angeles Times; "You can hear entire show by radio phone", February 19, 1922 Mansfield (OH) News. Actors Grace George and Herbert Hayes performed an entire play from a San Francisco station in the summer of 1922.July 1922 wire service story which appeared in the July 19, 1922 Lima (OH) News (under headline: "Acting by radio is a weird sensation") and the July 23, 1922 Charleston (SC) Daily Mail (under headline: "Presenting a play over the wireless in newest wrinkle")

An important turning point in radio drama came when Schenectady, New York's WGY, after a successful tryout on 3 August 1922, began weekly studio broadcasts of full-length stage plays in September 1922,New York Times and Hartford (CT) Courant radio listings, August 3, 1922; New York Times radio listings, September 11, 19, and 25, 1922; "Will Give Dramatic Productions By Radio" September 2, 1922 The (Fort Wayne, IN) News-Sentinel; Local Radio Fans to Hear "Officer 666" November 3, 1922 Fayetteville (AR) Democrat; "Madame X" From WGY Thursday Night, November 21, 1922 Fayetteville (AR) Democrat. using music, sound effects and a regular troupe of actors, The WGY Players. Aware of this series, the director of Cincinnati's WLW began regularly broadcasting one-acts (as well as excerpts from longer works) in November.Lawrence Lichty, "Radio Drama: The Early Years" in Lawrence Lichty and Malachi Topping (eds): American Broadcasting (New York, Hastings House, 1975). The success of these projects led to imitators at other stations. By early 1923, original dramatic pieces written specially for radio were airing on stations in Cincinnati (When Love Wakens by WLW's Fred Smith),April 2, 1923 Hamilton (OH) Evening Journal radio listing. Philadelphia (The Secret Wave by Clyde A. Criswell)"Writing radio plays is latest", May 27, 1923 Oakland (CA) Tribune. and Los Angeles (At Home over KHJ).April 22, 1923 Los Angeles Times radio listings; "KHJ Travels in Pretense Land", April 23, 1923 Los Angeles Times. That same year, WLW (in May) and WGY (in September) sponsored scripting contests, inviting listeners to create original plays to be performed by those stations' dramatic troupes."Contest for Prize Radio Drama Opens September 1", August 19, 1923 Washington Post; "G. E. Company Has Prize for Radio Drama", September 7, 1923 Waukesha (WI) Daily Freeman.

Listings in The New York TimesCompare The New York Times – Archive 1851–1980 and other sources for May 1923 reveal at least 20 dramatic offerings were scheduled (including one-acts, excerpts from longer dramas, complete three- and four-act plays, operettas and a Molière adaptation), either as in-studio productions or by remote broadcast from local theatres and opera houses. An early British drama broadcast was of Shakespeare's A Midsummer Night's Dream on 2LO on 25 July 1923.

Serious study of American radio drama of the 1920s and early 1930s is, at best, very limited. Unsung pioneers of the art include: WLW's Fred Smith; Freeman Gosden and Charles Correll (who popularised the dramatic serial); The Eveready Hour creative team (which began with one-act plays but was soon experimenting with hour-long combinations of drama and music on its weekly variety program); the various acting troupes at stations like WLW, WGY, KGO and a number of others, frequently run by women like Helen Schuster Martin and Wilda Wilson Church; early network continuity writers like Henry Fisk Carlton, William Ford Manley and Don Clark; producers and directors like Clarence Menser and Gerald Stopp; and a long list of others who were credited at the time with any number of innovations but who are largely forgotten or undiscussed today. Elizabeth McLeod's 2005 book on Gosden and Correll's early workElizabeth McLeod, The Original Amos 'n Andy: Freeman Gosden, Charles Correll, and the 1928–1943 Radio Serial. McFarland & Co, 2005. is a major exception, as is Richard J. Hand's 2006 study of horror radio, which examines some programs from the late 1920s and early 1930s.Richard J. Hand, Terror on the Air!: Horror Radio in America, 1931–1952 McFarland, 2006.

Another notable early radio drama, one of the first specially written for the medium in the UK, was A Comedy of Danger by Richard Hughes, broadcast by the BBC on 15 January 1924, about a group of people trapped in a Welsh coal mine.Richard Hughes, 'A Comedy of Danger' in 'The Invisible Play': B.B.C. Radio Drama 1922–1928 by Alan Beck. One of the earliest and most influential French radio plays was the prize-winning Marémoto ('Seaquake'), by Gabriel Germinet and Pierre Cusy, which presents a realistic account of a sinking ship before revealing that the characters are actually actors rehearsing for a broadcast. Translated and broadcast in Germany and England by 1925, the play was originally scheduled by Radio-Paris to air on 23 October 1924, but was instead banned from French radio until 1937 because the government feared that the dramatic SOS messages would be mistaken for genuine distress signals."Maremoto, a radio play (1924)", Réseaux, 1994, Volume 2, Numéro 2 p. 251–265

In 1951, American writer and producer Arch Oboler suggested that Wyllis Cooper's Lights Out (1934–47) was the first true radio drama to make use of the unique qualities of radio:

Though the series is often remembered solely for its gruesome stories and sound effects, Cooper's scripts for Lights Out were later recognised as well written and offered innovations seldom heard in early radio dramas, including multiple first-person narrators, stream of consciousness monologues and scripts that contrasted a duplicitous character's internal monologue and his spoken words.

The question of who was the first to write stream-of-consciousness drama for radio is a difficult one to answer. By 1930, Tyrone Guthrie had written plays for the BBC like Matrimonial News (which consists entirely of the thoughts of a shopgirl awaiting a blind date) and The Flowers Are Not for You to Pick (which takes place inside the mind of a drowning man). After they were published in 1931, Guthrie's plays aired on the American networks. Around the same time, Guthrie himself also worked for the Canadian National Railway radio network, producing plays written by Merrill Denison that used similar techniques. A 1940 article in Variety credited a 1932 NBC play, Drink Deep by Don Johnson, as the first stream-of-consciousness play written for American radio. The climax of Lawrence Holcomb's 1931 NBC play Skyscraper also uses a variation of the technique (so that the listener can hear the final thoughts and relived memories of a man falling to his death from the title building).

There were probably earlier examples of stream-of-consciousness drama on the radio. For example, in December 1924, actor Paul Robeson, then appearing in a revival of Eugene O'Neill's The Emperor Jones, performed a scene from the play over New York's WGBS to critical acclaim. Some of the many storytellers and monologuists on early 1920s American radio might be able to claim even earlier dates.

1930–1960s: widespread popularity Perhaps America's most famous radio drama broadcast is Orson Welles' The War of the Worlds (a 1938 version of H. G. Wells' novel), which inspired stories of a mass panic that, though greatly exaggerated, signaled the power of the form.Kristen Hare, "Threatened by radio, newspapers exaggerated 'War of the Worlds' panic", Poynter Institute, 29 Oct. 2013. By the late 1930s, radio drama was widely popular in the United States (and also in other parts of the world). There were dozens of programs in many different genres, from mysteries and thrillers, to soap operas and comedies. Among American playwrights, screenwriters and novelists who got their start in radio drama are Rod Serling and Irwin Shaw.