Raj Kapoor made his debut as a director with the film Aag in 1948. While the film received a mixed response at the box office, its musical score (in which the music director Ram Ganguli was assisted by Shankar and Jaikishan) proved to be quite popular. However, during the recording of some song for his new venture `Barsaat', Raj Kapoor had some serious differences with Ram Ganguly, the music composer of the film and decided to assign its music to Shankar who insisted on taking Jaikishan as his partner and thus came into existence the new pair of music directors(MD) named `Shankar-Jaikishan' who gave landmark, path-breaking and trend-setting music for the RK production `Barsaat' in 1949.
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Barsaat, when Raj Kapoor had some difference of opinion with original music director
Its that time they united with others and Shailendra too (but after promising shailendra, they did not kept the promise and its Shailendra who wrote a letter and the content used for other film sung by KK)
They are Asst.MD