The film starts off with the old, tired and worn out Vasudha Prasad (Vidya Balan) who is almost on the verge of collapsing on the streets of Bastar district. On the other hand, her old and weak husband Hari (Rajkumar Rao) is pouring his heart out to a doctor emphasizing on the fact that Vasudha did visit him wearing a red dress, something that the doctor rubbishes as his hallucination.
Amidst that time, he gets to know that Vasudha has set for heavenly abode. That’s when he visits his son’s home to do the last rites of his dead wife… only to be shooed away by his son. When everyone is fast asleep, he escapes with Vasudha’s ashes to be immersed in Bastar and not in river Ganga. But before leaving the home with the ashes, he leaves a diary for his son (and the audience) to tell the unknown tale of Vasudha. The 20 years flashback shows Hari leaving Vasudha within a year of marriage, but not before making his presence ‘felt’ in her life. Also to act as an everlasting memory, he gets a tattoo done of his name of Vasudha’s arm.
In the diary, Hari mentions about Aarav (Emraan Hashmi), the multi millionaire business tycoon and also an owner of a whopping 108 hotels! It was actually a love at first sight for Aarav the very moment he sees Vasudha, who works as a florist in his Mumbai hotel. Aarav gets impressed with her simplicity and selflessness so much that he immediately offers her a dream job in his plush Dubai hotel. After initial reluctance, she picks up the job. Love blossoms between the duo and they find solace in each other’s company.
Just when everything is going smooth, there re-enters Hari into the life of Vasudha. Hari then explains the reasons and the circumstances as to why he disappeared and why the police have mistaken him as a dreaded terrorist. Vasudha, who initially is mighty upset and angry at the very sight of Hari, then seeks Aarav’s help to free Hari from the police by proving his innocence. Despite this being a tough task, Aarav takes it up solely for his selfless love towards Vasudha. While accomplishing the task, a very unexpected calamity strikes Vasudha which completely shatters the lives of Aarav, Vasudha as well as Hari. What is the calamity that strikes the trio, will Vasudha and Aarav ever be able to marry each other and does Hari overcome his selfish ways to help his wife ‘unite’ with her real love Aarav… is what forms the rest of the story.