At the beginning, Izna, a porn star (Sunny Leone) is lying dead in the grass,but she says that she wants to ask forgiveness from somebody for her sins. Then the story goes back 6 months.
Izna, a porn star is hired by an intelligence officer Aayan Thakur (Arunoday Singh) and Security Chief Guru Saldanah (Arif Zakaria) to become a 'Honey-trap' and help them retrieve critical information from a dreaded assassin Kabir (Randeep Hooda). During this mission Aayan gets to know about Izna's previous relationships with Kabir when Kabir, himself used to work for the intelligence. Kabir was discovered by Izna during one of his missions where Izna was being used for drug-peddling in a pub, which she was unaware of. Kabir makes an entry in the pub, shoots and arrests the guilty drug-peddlers. He calls Izna who explains that she was innocent and doesn't knew about the goon's intentions, Kabir takes a coin from her and decides not to arrest her and Izna was allowed to leave. Izna started loving Kabir and followed him to his house and handed him a love letter written with her own blood. Both start loving each other but one day Kabir disappears without any word. Six years pass by and Izna did not find him despite of many tries.
After Izna agreed to do the mission, she was taken to a residential colony in Sri Lanka, to live where Kabir also lived with an identity of a musician. Izna was asked to act as Aayan's fiancee and was given a story of how they both met each other. Izna was asked to go to Kabir's house to introduce herself as his new neighbor however he shut the door on her face as if he does not recognize her. The very next day he came to her window and wrote "Sorry" on the glass with his blood but ran away as soon as a phonecall came. Kabir attacks Guru Saldanah's team but Saldanah, however, makes an escape and plans to stop the operation. Meanwhile, Aayan plans to steal the data from Kabir while Izna takes Kabir out of his house. Izna sends a letter to Kabir telling him that she wants to meet him, following which Kabir leaves his house. Aayan takes charge and moves to Kabir's house to steal the data however upon copying data from his laptop gives Kabir an alert to his phone seeing which he runs towards his house. Aayan escapes with the data through the window but later, he discovers that the data was fake. Izna disagrees to stop the operation and says that she will never forgive Kabir and will soon bring him down and thus, requests to continue the operation.
Kabir still trusted Izna and never had a suspicion on her but his trusted friend and right hand Sumit suspects her and warns Kabir about her. Kabir proposes to marry her and asks Izna to shift to his house and leave Aayan. Izna agrees to this but in the meantime Aayan starts to love Izna and gets angry upon hearing this and tries to stop her, but she claims that she will only be able to steal the data once she gets into Kabir's house. Next day she moves to his house and starts staying with Kabir. In the meanwhile Kabir asked Sumit to arrange for a priest for the marriage, who accidentally read an SMS to Aayan on Izna's phone which proved she was a spy. Sumit goes to kill Aayan but was killed in a gun battle. Aayan calls Izna for some urgent talk and expresses his fears that they can no longer play this risky game as when Kabir will find out that Sumit is killed, he will kill Izna. Aayan gives her poison and asks her to mix it in the drink of Kabir.
Meanwhile when Izna was not at home, Kabir goes to Aayan's house and discovers Sumit's Bluetooth on the verandah. To find more about Sumit, Kabir searches the house and ends up discovering a book inside Izna's bag which had pages marked on them and had a similar story that Izna told to Kabir regarding her meeting Aayan. This confirms Sumit's suspicion and Kabir waits for Izna. Izna returns and offers him coffee. Izna mixes poison in the coffee given by Aayan. Kabir tells Izna that years back, he left Izna for a sting operation but during the operation, he had discovered that the country's own officers, security forces and politicians were corrupt. Therefore, he had shortlisted them and then he had them killed.
According to Kabir, he was a patriot and not a terrorist. Kabir threw away the poisoned coffee and told Izna that the Guru Saldanah and his team is a fraud who would kill Izna as soon as they would get the hard disk containing the original data. He asks Izna to escape and offers her a new passport, tickets and a Swiss bank account from where she can withdraw unlimited money. Yet, Izna refuses and when Kabir hugs Izna and kisses her before their separation, Izna shoots him in his stomach. Kabir dies immediately and Izna runs away with the hard disk containing the original data. She goes to Guru Saldanah and hands over the hard disk to him. However, she is soon surprised to know that Guru Saldanah was a fraud and after the task she was supposed to be killed and Aayan was given this responsibility to kill her; later, Aayan changed his mind as he was in love with her, hearing that Saldanah tried to kill Izna but Aayan killed him instead.
Izna told Aayan that because of their fraud mission she killed an innocent person, that too, the love of her life who blindly trusted her. Izna says that she would prefer to die with Kabir rather than living with Aayan and attempts to leave with the hard disk. Aayan threatens to shoot Izna if she leaves the house, but still she leaves and then she is shot by Aayan from the back. Izna falls to the ground but when Aayan comes to check whether she died or not, Izna shoots him to death. Then finally Izna, herself, dies.
After dying, Izna's soul asks forgiveness from Kabir's soul who at once, forgives her. Izna tells Kabir that without him, heaven won't be heaven for her and with him, she won't be afraid to go to hell. Then their souls rests in peace.