The story starts with a girl being chased in a forest by someone. In the background train horn can be heard, as it seems that she has evaded her killer, the killer appears and strikes her dead. Quick cut to a woman (later identified as Mira, played by Chopra) us standing at High Road Station about to board a train. She is injured and intoxicated. The film shifts to 2017, a backstory develops on how Mira met Shekhar (Avinash Tiwary) in a friend's wedding. The song montage follows on how they fell in love and got married and moved to a house. The story moves forward to 2019, Mira while on a shopping spree notices a black car following her, she manages to escape and reach home scared only to have the perpetrator/stalker throw a rock with a message. She shows Shekhar the threat note that asked her to drop the case against some big guy Bagga or her life would be in danger. Shekhar requests her to not fight the case for the sake for their family that could soon be expanding as Mira is potentially pregnant. Mira against the advises of Shekhar ends up fighting the case and imprisoning Bagga and freeing a innocent man. She is being thanked by the man's parents when Shekhar informs her that the results were positive and they are soon going to have a baby. Quick cut to 7 months later a pregnant Mira is the car with Shekhar returning from a movie, she mentions how she plans to quit her job as a lawyer as it was her dream to have a baby. At this moment a car coming from right crashes into Shekhar's side badly injuring both.Cut to a week we see Mira consulting a doctor who informs her about her suffering from amnesia where her short term memory never gets converted into long term and thus she suffers from episodes of total blackout. Mira contemplates on how she doesn't has anything in her life to remember as after the accident she miscarried. To cope up the pain she started heavily drinking, she became so relied on alcohol that it eventually broke her marriage with Shekhar moving on and marrying Anjali. Mira rides the train every day being unemployed with the sole purpose of seeing Shekhar and Anjali in the home she used to once live in. While seeing her house every day from the train window she also comes across the happiest moment of her day where near Greenwich station stays a woman (same as the one from the start of movie, named Nusrat, played by Hydari). Mira is strangely drawn to this woman and her perfect life filled with happiness and love. Mira always sees this girl as the one she was before the accident. She sees her everyday and even though doesn't even knows her name she feels as though she knows this woman closely. We see Mira trying to get a new job but she fails when her PTSD strikes on being asked why she hadn't worked in past tear. She leaves the interview, buys vodka, and boards the train. She again sees Nusrat dancing in her room and contemplates on how happy and perfect her life is. She then meets her friend Priya (from the wedding) in a bar. They often meet and Priya helps Mira to come out of her obsession over Shekhar and they drink shots to make Mira forget about Shekhar whose Facebook update is a picture with his new wife. In a parallel scene we get to know that Shekhar and Anjali are troubled by Mira constantly calling Shekhar, he pacifies his wife as its her birthday and they end up taking a pic that Mira sees on Facebook.In present day we see officer Kunal getting report of a Nusrat John being missing from 2 days. Case is handed Officer Kaur(played by Kulhari) and she starts the investigation by questioning the people at the hospital Nusrat worked in as a nurse. Nusrat's colleagues were the ones filing the report and they mention how she had gone to her dance instructor's party with them only for them to lose track of her eventually. The police questions the dance instructor Rajiv who mentions that he dated Nusrat casually and hadn't met her that day. On questioning her dance mates, Officer Kaur gets to know about Dr Hamid proceed the psychiatrist that Nusrat used to go frequently to. On questioning him and watching the recording of his sessions with Nusrat, it's known that Nusrat was in an unhappy relationship, where her husband used to be abusive towards her. Also her dance instructor was never dating her. He also mentions on how one day after her dance session he had seen a unknown guy demanding money from Nusrat or he would have shown something to her husband Anand. When asked about it by Dr Hamid, Nusrat had replied that he was just an old friend. On questioning Anand on why he wasn't the one filing the missing report for his wife and seemed rather unaffected by the whole situation, Anand replies that they were heading to divorce because Nusrat was apparently cheating on him.The police then seem to have found a lead apparently in the dance studio basement where the mask wore by Nusrat and drops of blood are found. Cctv footage suggests that its Rajiv who forced himself onto Nusrat but its later found out its a different girl altogether and Nusrat had left the party almost immediately.In meantime we see Mira on the train the day Nusrat went missing. Mira narrates on how she felt something unusual about Nusrat that day, how she seemed upset. At this moment she sees a man embracing Nusrat, Mira is shocked to see that the man is not her husband and suspects that Nusrat is cheating. Before she can find out more the train moves and she loses the sight. Mira meets Priya and is constantly asking answers for why was Nusrat cheating. Mira and Priya end up taking a few more shots that enrages Mira more. The fact that Nusrat is cheating resonates with Mira as Shekhar had cheated on her with Anjali that ended up destroying her. In a drunken rage she opens her phone to record a video of her abusing Shekhar, but Priya stops her. While the video still recording we see Mira completely crashing down and explain how betrayed she feels by Nusrat's actions and how she wants to go to Nusrat's house grab her hair and smash her head in the table till she dies. Once alone and still unable to cope Mira reaches Nusrat's home. She rings the bell but no one answers then she notices Nusrat walking towards the pathway on the side of the house that led to the forest behind. We see her following Nusrat noticing same guy who blackmailed Nusrat clicking pics of Nusrat. She catches up to her then blacks out to return to high road station injured. She gets on the train and is completely intoxicated barely conscious only thing she sees outside the window are firecrackers bursting.Back in present day police have found Nusrat's body in the forest, with preliminary reports it seems her body was dragged to the spot where it was dumped. Cctv footage shows an intoxicated angry Mira. After Anand denied knowing her the police suspect that Mira might have murdered Nusrat as her citizen card is found nearby the body. The police trace her steps to Mira getting down at Greewich station at 6, to barge at Nusrat's door at 6.30. Then next she is seen at High Road station injured at 10.30. Having a previous history of alcohol abuse she becomes the prime suspect.Present day Mira wakes injured and heavily intoxicated at her home. She tries to recall but to no avail. She finds a message on her phone with unknown number saying that she was in the forest and Nusrat is dead. She then finds a video of her that she accidentally recorded explaining how she wants to kill Nusrat. Scared she attends her support group/class where she explains on how after miscarriage she started using alcohol to heal herself, and how she became so dependent on it that she often became violent and forgot about it. She mentions on how celebrating Shekhar's promotion at home she has a drink too many and wakes in the morning only to Shekhar tell her how she hurled him with a corkscrew when he asked to stop drinking. Over multiple such stories she mentions how she got drunk at Shekhar's colleagues party and abused the host that caused Shekhar to get fired, and how on being asked to sign divorce papers she becomes enraged and breaks the mirror to no recollection. She is scared something similar had happened that day with Nusrat and she might have hurt her in her drunken state. She concludes that she has to remember that one night as that could be the only way out. Post her session she meets Priya and before she can tell Priya anything, Kaur and Kunal show up asking her questions about that night. She lies that she doesn't recognize Nusrat, lies about her citizen card being stolen and lies about remembering anything about the night. This makes Kaur call her compulsive liar. Since they don't have evidence they can't arrest her, they leave Mira who rushes to her doctor only to profess that she might have murdered Nusrat in drunken rage. Mira also contacts Anand, only to know the guy she saw Nusrat with was her psychiatrist, to this Anand admits that he wanted to Mira because he had hired a PI to follow Nusrat and he wanted to know how will police react to it. Mira comes back home only to be troubled by how angry she was in the video, and thus she ends up contacting the unknown number to know what happened that night. She receives a call from someone saying for a price she can know what happened in the forest. She agrees. Before the unknown caller contacts back we see Kaur coming down to force her to plead guilty. Kaur explains that all evidence are against her and being a lawyer herself she should confess instead of trying to delaying investigation by bringing up the the psychiatrist. In meantime Kaur gets a call that explains that at time of death Nusrat was pregnant and also that Mira's blood was found nearby. Mira is to be arrested immediately but she requests to bring her medication from the washroom. Once inside Mira panics only to jump from her bathroom window. As the police barge inside the bathroom, Mira is seen escaping unharmed by the fall as she landed on a pile of garbage bags. She runs and evades the police only to notice she had dropped her phone that got picked by Kaur. Now on the run, to prove her innocence she meets the guy she saved from trial in start of the movie. She requests him some money, phone and a gun. She uses the gun to threaten Dr Hamid. He explains that Nusrat had called him over because she got to know the same day that she was pregnant but the baby wasn't Anands. He didn't know whose it was but she was texting him and was supposed to meet him that evening to sort it out. To find more clues about this new person who could have potentially murdered Nusrat she sets to the forest. There at the edge of the forest she finds a horse ranch whose owner denies seeing her or Nusrat ever. Back at police station they find from Mira's phone that someone was extorting her for money. Kaur asks the data to be backed up and the phone be returned to her. Mira is the station where she is unable to use her pass as its out of balance. When she goes to gets it recharged the technician mentions that her last trip was from High Road to Redford at 8.30 pm. She doubles checks with him before leaving. Meanwhile police know that she has been spotted at the train station and start searching for her. Mira in low profile attends the prayer service for Nusrat, where she notices an altar with her pictures, there she sees a picture of Nusrat's phone and recalls the ranch boy having the same phone. She retrieves Nusrat's phone and sim from the ranch boy. While exiting the station she comes across Shekhar's ex boss Zahra and her husband, she apologizes to them for her behavior. They seem have to no recollection of it, on insistence they tell her that that day at party she felt puckish so she napped in their study, while towards the end of the party She noticed how violent and aggression Shekhar got on Mira. On asked about Shekhar being fired, they tell Mira it had nothing to do with her but because of Shekhar's inappropriate behavior towards a female coworker. Zahra concludes that she was glad when she got to know about the divorce. This comes as a realization to Mira on how all her episodes of rage were tales fed to her by Shekhar and how Shekhar created scenarios, forced her to drink, injured himself or her and made her think that it's her fault. Shaken to the core by this revelation Mira stops consuming alcohol. In meantime she gets Nusrat's phone to work only to find that she was having an affair with Shekhar. She goes to High Road station to confirm her doubts and Cctv confirms her presence at the station 8.30 not 10.30. She asks about who provided the tape to the police and gives the technician money to keep her posted on the same. She contacts the PI hired by Anand, he turns out to be the person who was blackmailing Nusrat regarding sending her pics with Shekhar to Anand. He was also present that day in forest and was the one to ask Mira for money. Mira is about to meet the PI Walter when suddenly a car comes at hits him killing him. Before he dies he mumbles something about his house to Mira. Mira grabs Walter's phone and threatens Anand to give her Walter's home address or she will tell the police about him spying on his now late wife. Mira texts someone from Walter's phone saying that proof is at his house. Once at Walter's house she sees all the prints of her and Shekhar and Nusrat in the forest. She calls Shekhar from Nusrat's phone only to have Anjali picking up and abusing Mira for calling. Once Shekhar comes on phone Mira connects on how all this while he had saved Nusrat's number under her name. She tells him to meet her at Walter's home, as she knew about him being the father. Shekhar comes and tries to play dumb. To this Mira threatens him with the gun, he finally accepts that he had an affair with Nusrat, they worked at same hospital. They always met in the forest. It was same that day too but Mira came there and confronted Nusrat. Nusrat escaped and ran to him. This made him angry and he hit Mira multiple times finally pushing her on a rock that injured her and made her bleed. Once unconscious he returned to Nusrat. When she told him about her pregnancy and refused to get the baby aborted Shekhar in rage strangled her. She was threatening to get him arrested on the grounds of sexual exploitation. Concluding the story he offers Mira vodka planning to manipulate her again, this time Mira doesn't fall foe his trap, he requests her to give him Nusrat's phone she agrees only to hit him and knock him unconscious. Then as a major plot twist it turns out Shekhar hadn't actually murdered Nusrat, as he didn't have a motive to murder Walter. In flashback Mira is seen rummaging through photographs that Walter took only to remember that the car that hit him was same car she had seen before too. On running the license plate it turns out the car belonged to Jimmy Bhalla the culprit of her last court case. He had committed suicide in prison and while searching his images she gets to know that Kaur is his daughter. It was at this moment that Kaur comes in with a gun in her hand. Explanation ensues and Kaur tells that her father was wrongly accused by Mira because of which he died. And post his death she took upon herself to avenge and spoil Mira's life. She was the one who threatened her, crashed her car in the accident. And when she saw one day travelling in train she started shadowing her. That day she was at the forest too, and wanted to murder an unconscious Mira but unfortunately Shekhar hadn't murdered Nusrat, he had barely suffocated her to unconsciousness but panicked about it and had left While Kaur was trying to murder Mira, Nusrat gained consciousness and saw her in the act. So while Kaur pursued and killed Nusrat, Mira gained consciousness, walked to the nearest station and took the train only to notice Nusrat being chased through the forest. This was her plan to frame Mira. But Mira concludes saying that she couldn't be framed as she already knew Kaur's role in this as she had received proof from high road station CCTV tech that it was Kauai who bungled the footage timing, and she knew that Kauai had her phone so she intentionally sent the text to her phone from Walter's phone after his death. A fight ensues between them that ends up in Kaur accidentally shooting herself. Back to present Mira takes Kaur's gun and places it in an unconscious Shekhar's hand to make it look like he murdered her. Police arrests Shekhar and Anjali breaks up with him.The movie ends with Mira paying respect to Nusrat's grave and the taking a new train to a new journey.