It is now finals week, but Quentin is still obsessed with "Song of Myself" and Margo's location clues. At dinner, Quentin's parents wax nostalgic about his upcoming graduation and his mother tries to give him perspective on Chuck Parson and the educational difficulties that might cause him to act out. His parents talk about people as mirrors and windows - noting human inability to really see people - and Quentin realizes that he has never really tried to see Margo as a person.
On Tuesday, Quentin, Lacey, Ben, and Radar all go to the mini-mall together after school. They again go directly to the office room, where they suddenly hear footsteps approach. Two young men enter the room, revealing themselves to be Gus, the security guard from the SunTrust Building, and a friend. They go by the pseudonyms "Ace" and "The Carpenter." They reveal that they are "urban explorers" and that they saw Margo here often and took her on exploring trips when she was as young as 13. However, they note that she never really wanted to explore but rather stay in these abandoned buildings, writing in a black notebook. In the course of this conversation, "The Carpenter" calls Lacey a bitch, which causes Ben to punch him until Quentin and Radar pull him off. The two men flee and Quentin, Lacey, Ben, and Radar continue looking for clues. Quentin finds a stack of brochures for subdivisions, including one for the pseudovision "Grovepoint Acres" which Quentin had explored previously along with another, "Collier Farms," which is on his list but hadn't been visited yet.
That Friday, Quentin tells his mother that he is going to a concert and instead sets off to visit Collier Farms. This pseudovision is overgrown and impassable by car, causing Quentin to get out and walk through the mud to look around for hiding places. Finding nothing, Quentin drives to the last pseudovision on his list, "Logan Pines." When Quentin is almost there, he gets a call from Ben reporting that Radar's parents are abruptly going out of town to buy a newly available collection of black Santas and so he, Radar, and Quentin will be hosting a party that night. Ben scolds Quentin when he hesitates, so Quentin promises to come over after visiting the last pseudovision and rushes through this visit, finding nothing at all.
At the party, Quentin helps Radar put away the nicer black Santa paraphernalia and discusses kissing with Ben until Lacey interrupts to quell Ben's fears. Rather than the drunken debauchery of the last party scene, this party turns into a sober but joyfully nostalgic story-telling session. When Quentin gets home for the night, his mother tells him "I really like being your mom"(p.215) before he heads to bed with "Song of Myself." Quentin becomes infuriated thinking over the fruitlessness of his pursuit of Margo, ripping his maps off the wall and then punching his pillow after accidentally stepping on one of the tacks. However, as he falls asleep he realizes that the empty tack-marks on his wall look just like the ones on the wall of the abandoned building, meaning Margo must have been plotting a discernible route.
In the morning, Quentin convinces Radar to accompany him back to the abandoned building. In the souvenir shop, Quentin finds a map with holes in it that seem to match those on the wall in the other room. The hole-marks are ripped and vague, meaning it's hard to pinpoint where Margo was planning to go and that she didn't intend this map to be a clue for Quentin to use. Two un-ripped dots mark Los Angeles and Chicago and a ripped one marks a borough of New York City. Another dot is in New York State, not near the city, where many potential small towns exist. The last dot is over somewhere near Washington D.C. or north Virginia. Though they have learned a lot, the possibilities seem too expansive to make a plan. They return home to study for finals; Quentin, still distracted by thoughts of Margo, chats online with Lacey, Ben, and Radar as well about Margo's black journals and potential routes she could be following.
On Monday, Radar reveals a program he has written so that one can skim the first lines of any Omnictionary articles within a chosen category. Ben approaches them and reveals his own Margo-related homework: he and Lacey plotted every possible trip between the five points on Margo's map and have come up with the idea that since round-trip it is exactly 23 days to hit each point in order, Margo must be planning to return for graduation. Quentin doesn't believe this hypothesis, but ponders it nonetheless and returns to reading "Song of Myself" after school. The next day, Quentin takes more finals and thinks about the "lastness"(p.227) of going to school in the few remaining days of his senior year, viewing things through his the lens of his own experiences at school and the ones he empathizes with Margo having seen and felt. Quentin becomes suddenly upset while cleaning out his locker and pushes everything into the trashcan before setting off to run all the way home. Experiencing this feeling of leaving and not looking back, Quentin decides that Margo is definitely not in Florida and is definitely not planning to come back.
For the next two days, Quentin keeps trying to understand where Margo might be. On Friday morning, the day of graduation, Quentin's parents come in in the morning with a gift. They give him a small box with a key inside - a key to a car that, though a used minivan, is all Quentin's own. Quentin decides that he will drive himself to graduation and informs Radar and Lacey of the development over instant messenger. Radar asks to drop off 212 leftover beers in a cooler in Quentin's car, which Quentin agrees to before signing offline to shower. Still thinking of Margo's trip throughout his shower, Quentin gets out un-soaped and types a zip code near Catskill Park in New York (the approximate location of the fourth map tack) into Radar's Omnictionary program. Skimming through results, Quentin stumbles upon the entry for Agloe, New York. Agloe was originally "a fictitious village created as a copyright trap or paper town"(p.235) but later became real through the building of an "Agloe General Store"(p.236) in the location where the fictitious village was drawn to be. Clicking to the comments section, Quentin finds a posting from an anonymous user - "fyi, whoever Edits this -- the Population of agloe Will actually be One until may 29th at Noon"(p.236). Quentin realizes from the unusual capitalization that Margo posted this, and springs into action.
Quentin calls Radar and Ben frantically while getting dressed and mapping online a path from Orlando to a town near Agloe, New York. Driving a constant 65 miles-per-hour, the trip takes just over 19 hours. Looking at the time, Quentin sees that there are just less than 22 hours until noon of May 29th. Quentin decides that he has to drive there because flights are too expensive and won't get him close enough anyway. Radar convinces him to wait until walking in graduation and dropping off the beer, but Quentin decides he only has time to find his parents and explain briefly what's going on. On his way back out to the parking lot, Quentin sees Ben, Lacey, and Radar sitting in the car. Quentin tries to hurry them out, but they respond that they are coming on the trip too.
Fairly late in the book, Green introduces the paired motifs of mirrors and windows through a conversation Quentin's parents have at dinner. Mirrors represent human inability to see oneself truly and to show others themselves truly; windows represent the inability to see others truly, specifically as humans who are flawed like us. Looking back and forward in the book, Quentin first sees Margo through his window on the night they go for their adventure and will see Margo through a window-like object when he finds her in Agloe. These two moments, along with many others, show Quentin's inability to see Margo as anything less than a perfect miracle, no matter his supposed revelations about her humanity and inner self.
In that vein, this section contains repeated feelings of breakthrough for Quentin. Each time he reaches a new realization, about Margo's maps, the meaning of "Song of Myself," etc. - he is often either misunderstanding Margo or truly understanding himself a bit better. For example, Quentin he runs out of the school building after throwing everything from his locker in the trash and decides that his feelings of getting away from something must be what Margo had been and is feeling about getting away from Florida. While he does seem to be having a moment of revelation for himself, recognizing his oft-suppressed feelings of wanting to escape routine and childhood - this does not mean that he truly understands Margo any more. Again, this may be read as a moment in which a male character forces his own feelings upon a female character.
Margo's special capitalization is the final clue that leads Quentin to find her in Agloe. This is special because it is an important piece of her identity - feeling the need to assert justice even in the silly case of capitalization of words internal to a sentence. Margo wants to shake up the order of things, but at base is trying to be sympathetic, almost empathetic, to the world. She is also an experimental writer - someone who would rather write in her black journal than explore in an abandoned building. Finally, she has a flare for the romantic - writing the entry on Omnictionary at all. This mix of childish, adult, eccentric, and reasonable traits lead to her being found by Quentin, though he does not see their complexity but rather the single image of Margo as defined by this special language choice.
Ben and Lacey are sure that Margo is actually going on a 23-day trip around the US, only to return in time for graduation. As happens throughout the book, this demonstrates the ability of people close to Margo to completely misconstrue her personality and plans, shaping them to their own ideas of her and then believing in them fervently. The pursuit of Margo also brings Ben and Lacey together, meaning that to a large extent they will feel like Radar expresses when they find Margo - that they like the clues and the chase better than actually finding her.
Green parallels himself and Quentin in the book to some extent - as Green owns up to on his Youtube channel Vlogbrothers, he is and grew up as a nerdy boy. To this end, Green often writes what he knows - philosophical high school nerds with intense crushes on eccentric and beautiful girls. This parallel goes further in Paper Towns because the situation is even based on something from Green's life - having sought out a real paper town while on a road trip with a friend during college. Green both understands Quentin's flaws, since he has spent a lifetime thinking about them, and may still be blind to a few of them. Green surrounds Quentin with friends on the trip to find Margo, still making it a fun and exciting literary experience rather than a thoughtful pursuit to find Margo's true self, which parallels the casual nature of Green's own road trip experience. However, this foreshadows the fact that, like with Green's own experience, only a nostalgic memory was left behind after the journey.