The still is most likely from her swan-song Raat Aur Din, which deals with dissociative identity disorder. Nargis won the first ever National Award for Best Actress for this role, in 1967.
Via Filmi Geek's review, "Nargis's performance, though, stands out and makes the film worth watching. Apart from one instance of classic movie-madness " wild cackling giving way to violent sobbing " she presents a chillingly engaging portrayal of her character's split personality. Her Varuna is sad and troubled; though unaware, consciously, of her illness, she nevertheless appears melancholy and ill-at-ease, as though the demons that drive her nighttime excursions swirl precariously just below the surface. And her 'Peggy' is not a care-free party-girl; there is a desperation in her thirst for alcohol, music, and stimulation that is palpably pathological. Raat Aur Din is Nargis's film, and it is a showpiece for her skill."
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