Ghazab (1982)

Ajay alias Munna Babu is a semi-senile, gentle but naive young man who has a wealthy family estate. His employees and alleged well-wishers conspire against him and introduce him to his long-estranged mother, Shakuntala, and brother, Vijay. Munna is overjoyed, not knowing that they are devious impersonators. This joy is quite short-lived, as they soon show their true colors, and Munna gets killed. His restless spirit seeks out his real brother and appeals to him to avenge his death. Vijay, at first, thinks he is hallucinating, but when his mother confirms that he indeed had a twin brother, he agrees to accompany Munna's spirit back to where he was killed, and thus assist him complete his vengeance. Things do not go as planned, and Vijay himself becomes their victim, and may face the very same fate as Munna.