Mike Bondy tells the stories behind some of the best-loved songs in the history of popular music and discovers that one was plucked from obscurity, while others were nearly ditched altogether.

UNCHAINED MELODY Unchained Melody is undoubtedly one of the most successful romantic songs in the history of popular music and it's sometimes hard to believe that its origins lay in a fairly obscure 1955 American prison movie called Unchained.

Directed by Hal Bartlett, the film depicted life in the California Institute of Men, a state prison at Chino, and was based on a book written by Kenyon J. Scudder, who had been a supervisor there.

The film was released in January, 1955, with music written by songwriter and composer, Alex North. Lyricist Hal Zaret then added the words and a slice of pop history was born.

It was sung in the film by baritone Todd Duncan, who had previous success in George Gershwin's Porgy and Bess. On the film soundtrack, though, a blind black singer call Al Hibbler performed the song and it went on to be nominated for an Academy Award. Surprisingly, it only finished fifth in the voting with Love is a Many Splendoured Thing taking the Oscar.

Hibbler's version was simultaneously released in America with an instrumental recording by Les Baxter and both rocketed up the Billboard charts, each selling over a million copies. They did well in the UK too, but sales were outstripped by British crooner Jimmy Young, whose version went to number one for three weeks in June and July, 1955.

Ten years later the Righteous Brothers recorded the most famous version of the song, but it was released as a B-side in America to Hung on You. The radio stations over there quickly wised-up and flipped it over, sending Unchained Melody into the top ten, while in Britain it reached number 14.

A quarter of a century on, in 1990, someone had the bright idea to include it in the film Ghost, which starred Patrick Swayze and Demi Moore. It provided the background music to the famous erotic pottery scene in the film and the public lapped it up. It soared to the top of the UK charts, staying there throughout November, 1990.

In 1995, Robson & Jerome from ITV's Soldier Soldier series sold nearly a million and a half copies of the song and their version had a seven-week run at the top of the charts. In 2002 Pop Idol runner-up Gareth Gates also went platinum as his recording hit number one in the UK.

Almost 700 artists have recorded Unchained Memory, making it one of the most covered popular songs ever.

MOON RIVER When Henry Mancini and Johnny Mercer joined forces to write the music for the 1961 movie Breakfast at Tiffany's it was always likely that the marriage of these two legendary songwriters would produce something quite out of the ordinary.

They were asked to present a song for the movie that would suit the fairly limited vocal range of main star actress Audrey Hepburn, who was neither an accomplished or established singer.

They came up with an absolute masterpiece in Moon River. The song plays an integral part in the film, with Hepburn's scatty playgirl character (Holly Golightly) sitting out on the fire escape of her apartment with a guitar in hand giving a very simple but highly emotional rendering of this classic song.

She is discovered singing it by her co-star George Peppard, who plays struggling writer Paul Varjak. The movie is a comedy romance which was slightly watered down from the celebrated best selling novel by Truman Capote.

The famous "My Huckleberry friend" line from the song has plenty of people guessing as to what it actually means, and many think it may have its origin in the works of American writer Mark Twain (The Adventures of Huckle-berry Finn).

In the film though, the two characters steal a couple of cheap face masks from a store and George Peppard's one happens to be that of a cartoon character Huckleberry Hound, so it may be a reference to that.

Legend has it that the studio bosses were keen to axe Moon River from the finished film, only for the star Audrey Hepburn to say "over my dead body", or words to that effect. This was a wise decision because it won an Oscar for best film song, adding yet another accolade to the work of Henry Mancini and Johnny Mercer.

In America, hit versions of the song appeared in the Billboard charts for the soul singer Jerry Butler and Henry Mancini himself, but here in Britain, South African-born singer Danny Williams, whose voice invited comparisons to Johnny Mathis, made a recording of Moon River for the HMV label.

His definitive version stormed into the UK charts, staying there for a lengthy 19-week spell and reaching the coveted number one spot in Christmas week 1961.

The artist who has most closely identified with it over the years, though, has been American singer Andy Williams (no relation to Danny), who not only used it as the theme for his own TV variety show, but then proceeded to name his production company and theatre in Branson, Missouri, after the song.

Over the Rainbow Metro_Goldwyn-Mayerwere undoubtedly the most successful film studio in the 1930s and it was their output of glossy musicals which played a crucial part in keeping them up there as leaders of the pack.

Arthur Freed was a prolific lyricist of many a hit song in Hollywood during this period and was just turning his hand to a second career as a film producer.

He had noticed the tremendous audience reaction to Judy Garland in her third film, Broadway Melody of 1938, especially when she had sung Dear Mr Gable/You Made Me Love You, and he was determined to find a project which would turn her into a major star.

He saw the potential in L. Frank Baum's tale, The Wonderful Wizard of Oz, but the studio head Louis B. Meyer wanted to "borrow" 11-year-old Shirley Temple from 20th Century Fox to take the lead role of Dorothy.

The studio refused to release her, so the door was now open for Judy Garland to take it over, although she was 6 years older than Shirley and many felt simply too old.

Harold Arlen was called upon to provide the music for the movie, with Yip Harburg providing the lyrics, and these two very successful writers worked hard to come up with songs which integrated perfectly into the story-telling process. Over the Rainbow was used early in the film when Dorothy longs to escape her dreary life on a farm in Kansas.

After an advance screening, several MGM executives expressed the opinion that the film was too long and suggested that Over the Rainbow be cut and removed altogether as it slowed down the action too early in the film, but after heated discussion Arthur Freed persuaded them otherwise.

The Wizard of Oz was rightly nominated for six Academy Awards in 1939, but had the misfortune to be up against Gone With the Wind, which swept the board. Over the Rainbow, though, did win the Oscar for best film song and sold over a million copies on disc.

Sheet music sales also did well, and in countless polls down the years, Over the Rainbow nearly always comes out as number one when the top songs from films are voted on.

Versions through the years have been heard from, among others, Glenn Miller, Ray Charles, Johnny Mathis, Tori Amos and Harry Connick Jr, but most notably in recent times from the late Eva Cassidy.