Bambai Ka Babu
Ever heard of a Hindi film where a man falls in love with his own sister? Dev Anand tried the concept here. After getting involved in the murder of his friend in Bombay, Dev Anand escapes to meet the friend's family in a village in Punjab.
He lets the family think he is the friend, then discovers the friend's beautiful sister (Suchitra Sen). He falls in love with her, and hates it when she calls him bhaiya (brother). And yes, the lyrics to Mukesh's all-time popular number Chal ri sajni ab kya soche are worth memorising.