how to copy 80s Hindi movie and remake it as "ghajini"

1980's movie called, "Pasand Apni Apni", directed by Basu Chatterjee,

Actors, the great Utpal dutt, Mithun Chakraborthy, Rati Agnihotri.

I felt so sad that A. Murugudas copied the entire story, including dialogues, screenplay, translated to Tamil and remade it as the 1st half of Ghajini, I cant comment on the 2nd half.

Its a pity that this Tamil movie was remade into Hindi, how strange.