Buddha Mil Gaya (1971)

Two unemployed slackers, Bhola and Ajay come across a newspaper advertisement about a missing elderly gentleman, whose estate is worth millions. They come across this male in the Hanging Garden Park in Bombay, and decide to make him their paternal uncle and take him to live with them in a rented apartment, which they cannot afford. This elderly man, Girdharilal takes an unusual interest in Ajay's girlfriend, Deepa. While Bhola and Ajay try to find ways and means of getting rich by turning Girdharilal in, a number of horrific homicides are committed, all against former business associates of Girdharilal, and the clues all point toward the hapless duo.