Sitting down for a meal, the girl, whose name is Lucy, learns Indian words and customs. She asks how to say "taxi" and Saroo goes into the kitchen where he sees some jalebi. Suddenly, he remembers his brother, and begins to eat the sweet treat. Lucy comes in and notices that he seems out of sorts. "I'm not from Calcutta," he says, "I'm lost."
Sitting down with his classmates, Saroo tries to piece together his personal history. He recalls that the train platform he fell asleep on had a big rain tank and was not many stops from his home. One of his classmates recommends he try Google Earth to find his home. Another asks if his parents tried to find him, in which case there might be a paper trail, but they think this is unlikely, given that Saroo does not know his last name.
On the walk home, Lucy tells Saroo that her mother died about four years prior, and that her father is mad at her mother for refusing chemo. "But she just knew herself, you know?" Lucy says. She asks Saroo what he thinks about their classmate's idea to create a search radius and he begins dancing in a silly way.
We see them in bed together, later. While touching the sleeping Lucy's hand, Saroo has a flashback to eating a mango with his mother as a child. Saroo sits up in bed and looks out the window, before logging on to Google Earth and beginning to search for where he might have come from.
2010, Hobart, Tasmania. Lucy and Saroo are visiting Saroo's parents and she invites him to come for a run. He chases her up a hill, and they laugh as they go. At the top, Saroo has a vision of his younger self on a nearby mountaintop. Back at the house, Sue and Lucy look at pictures, including a picture of Mantosh. "He's been hard to control, but very very smart, and, I mean, he could do anything if he just learned to control that energy," Sue says.
At dinner, Sue, John, and Lucy discuss all of Saroo's athletic trophies. Mantosh comes in from having a cigarette, and Lucy wants to tell Saroo's parents about the fact that he wants to find out more about his origins. Saroo does not want to, which upsets Lucy. Mantosh begins to taunt Saroo about wanting to be an expert and Saroo insists that he is different than Mantosh. Mantosh begins hitting himself and erupts in a tantrum like when he was a child.
"I hate what he's done to you," Saroo says to Sue when Mantosh leaves the table, and Sue gets up from dinner, angry. We see a flashback of Saroo's birth brother calling for him at the train station.
Saroo and Lucy return to Melbourne. At a party, Lucy wants to dance, but Saroo does not want to. She tries to get him to be emotionally honest with her, but he resists, angry. They get in a fight in which Saroo tells her that it is painful to know that his mother and brother have likely spent 25 years looking for him. "I have never stopped you. I want to help," Lucy says, but Saroo tells her he wants to break up.
Saroo begins searching for his family more actively, hanging maps on the wall of his apartment to trace his migration through India. He works tirelessly to try and figure out which train he got trapped on and manages to locate the rain tower he remembers. We see a flashback of his mother searching for him on a beach.
John visits Saroo and invites him to come home, telling him that Mantosh is missing. He references the fact that Saroo has left his job and tells him that he and Sue are worried about him, but Saroo does not answer. At the mall, Saroo sees Lucy on an escalator, and they go and talk on a beach. He tells her that he has been visiting his mother in his imagination. "What was she like?" Lucy asks, and Saroo says, "Beautiful." He asks her how New York was, and she tells him she's come back because her funding came through.
Saroo tells Lucy that he misses her, and she tells him that Sue is not doing well and needs to see him. Saroo has a memory of bringing a watermelon home and getting hit by a scooter as a child. The scene shifts back to Lucy and Saroo lying down, as she asks him what he will do if he finds his family, but they are no longer there. He tries to kiss her, but she leaves him.
Reminded of his Indian heritage at college, Saroo begins to have flashbacks to his early childhood. At a dinner at a classmate's house, he spies some jalebi on the counter and he remembers his brother and their relationship before he got lost. It is a disorienting moment, a flood of unexpected memories that send him back into the past in the blink of an eye. It is in this moment that Saroo realizes that he has many memories buried deep down that he has never explored, as he has been so busy integrating himself into the society that he was adopted into. This marks yet another turning point for Saroo.
At school, Saroo also finds some comfort in the romantic companionship of Lucy. They share a goofy playfulness and enjoy one another's company. She is compassionate about his situation and wants to help him figure out where he comes from, while also sharing her own struggles with having lost a parent. The two of them share a special intimacy, which provides Saroo with some balance throughout the emotionally overwhelming process of uncovering his origins in India.
Once he has opened a portal to the past, Saroo begins experiencing more and more memories of his early life. They come to him in flashes, almost as though they are haunting him, and he must slowly piece together their meaning, with the help of trusted confidants. For the first time in his life, Saroo feels the full extent of his displacement, the emotional toll it has taken, and the ways it has left a hole in his sense of self. He sees that his life has been blessed, but there are mysteries that he still wants to solve.
At some point, Saroo's unresolved searching gets the better of his mental health and starts to take a toll on his relationships. He disparages his brother and gets into fights with Lucy about the fact that he has lived in privilege while his birth family has struggled to find him. Saroo feels a great deal of grief about his unusual situation and wants to figure out a way to reckon with it, while feeling powerless to connect meaningfully with where he came from. In spite of their good intentions, the people in his adult life cannot help him find the peace he is searching for as he confronts this crisis of identity.
Director Garth Davis shows Saroo's journey into the past by splicing together footage of him in the present with images of his childhood in India. One moment we see Saroo walking on a bridge in Melbourne, the next we see him as a child somewhere. Streets from both countries meld into each other, edited together in a filmic collage that reflects Saroo's mental state, his search for answers and a sense of being in-between selves, in between cultures. Davis makes sure to align the viewer with Saroo's psychological experience throughout the film.