Manu (Ayushmann Khurrana) is the owner of a gym in Chandigarh, and also a bodybuilder, preparing for an annual competition, titled "G.O.A.T" (Gabru Of All Time). Unfortunately, his gym fails to attract clients. Manu lost the last yr title to Sandeep Kasaana aka Sandy (Abhishek Bajaj), who runs a popular gym business in Chandigarh. Partner Jomo (Gautam Sharma) has the idea to hire a Zumba instructor to increase the client base. 3rd Partner Rizwan "Riz" (Gourav Sharma) is not supportive of the idea. Sandy and Manu are both students of Guruji (Yograj Singh). Sandy is miles ahead of Manu for this yrs title as well.Manu lives with Braj Munjal (Aanjjan Srivastav) Manu's grandfather, Naveen Munjal (Girish Dhamija) Manu's father, Mrs. Munjal (Soniya Bhatia) Manu's mother, Preet Munjal (Tanya Abrol) Manu's sister, Meet Munjal (Sawan Rupowali) Manu's sister. Mrs Munjal died 17 yrs ago. Naveen has am affair, but cant marry her due to pressure of family humiliation. Naveen wants Manu to help out at the family shop selling toilet-ware, but Braj supports Manu in his dreams and ambitions as a fitness provider. Manu is 30 yrs old and his sisters are worried if Manu is gay.A Zumba instructor named Maanvi (Vaani Kapoor) walks into the gym and things start looking up, financially. The Zumba classes succeeds in fetching clients to the gym. Maanvi is the daughter of Brigadier Mohinder Brar (Kanwaljit Singh), and is from a rich family. But she works for her own identity. For some reason Maanvi's mother Navjot Brar (Satwant Kaur) has shunned her and she is not even invited to family functions such as the wedding of her cousin. Manu injures himself while training. Maanvi takes him to the hospital and then drops him home. The entire family meets Maanvi and see how hot she is.As a thank you, Manu asks Maanvi out for Lunch. She is hesitant, but her friends (including Akshita (Karishma Singh)) encourage her to go for it. Maanvi asks Manu to train in Zumba for GOAT. Manu invites Maanvi for his Holi party and his sisters join Maanvi's Zumba class. Maanvi is very hesitant to move things along with Manu. Manu is attracted to Maanvi, and as they are about to have their first kiss (at the Holi party), the latter tells him that she has something to tell him. However, at that juncture, Manu refuses to hear her out, and eventually they form a sexual relationship with each other. Manu's family members also like Maanvi, as she is sophisticated and well spoken. His sisters, Preet and Meet, encourage him to propose Maanvi and marry her.When Manu eventually expresses his intention of getting married to Maanvi, she tells him that she is a trans-girl. A flabbergasted Manu asks "what's that?", and as he listens to Maanvi's explanation (she was born a boy Manu Brar and lived like that for 20 yrs and then got surgery to become a woman), he becomes enraged, and tells her that he's going to seek revenge for her actions. Manu is disgusted with himself because he keeps thinking that he "has had sex with a man." His friends in the gym, use derogatory terms like "chakka" to refer to Maanvi, which further infuriates him. Manu starts avoiding Maanvi. Maanvi continues taking her classes at the gym, but Manu asks Maanvi to leave Chandigarh and get out of his life forever. Maanvi refuses as she has faced bullies all her life and never backed down. Manu is under pressure from his family to marry Maanvi. He asks Maanvi to reject him, but she says that Manu rejected her and so he should face up to his family. She tells him to tell his family the truth about her.Despite the fall-out between the two, they continue to have feelings for each other. Maanvi did not share a close bond with her mother, but her father had accepted her for who she was, and was proud of her. He comes to visit her in Chandigarh, and they have a heart-to-heart conversation about what is bothering her, and suggests that she stops going to the gym for a few days. To this, Maanvi questions why she is the one who needs to leave everything behind or hide herself to seek solutions to her problem.In the meantime, Manu educates himself regarding trans-women, by watching videos of trans-women, interacting with a trans-woman personally, and also seeks counseling along with his friends to come to the conclusion that his relationship with Maanvi is by no means, "abnormal." Being born in a male body was a biological defect that Maanvi had already rectified via surgery, and only Manu had to step up and accept her for who she was.In the meantime, Manu's sisters find out the truth about Maanvi's past (Manu was being frustrated and to figure out why they follow Maanvi to her clinic where she goes for periodic checkups and to refill her prescription), and insults her in public in front of her entire Zumba class (when Manu was not in the gym). As a result of the public humiliation, she is about to pack her bags and leave Chandigarh when she receives a phone call informing her of her father's heart attack. She rushes to the hospital, where Manu also shows up. He tells her that he wants to be with her, and even stands up to his family members (Mamaji (Tarsen Paul), Mamiji (Goni Sagoo)) for Maanvi. Manu tells Maanvi that he has understood that the past doesn't matter and it only matters who she is today and that he loves her. Manu's family threatens him to come back but Manu defends Maanvi and points out their own flaws to them, including his father's own affair.The next day, Manu is seen competing for the title of "G.O.A.T". Manu competes but trails Sandy by a big margin. Jomo texts Maanvi that Manu needs her. In the last round of the tournament, Maanvi shows up to root for him. Being encouraged by her presence, he lifts up extra weights in a "clean and jerk", and wins the competition. After his victory, he asks Maanvi in front of the crowds, if she wants to be with him, and she says yes.