The episode plays out almost exactly as the previous episodes, with the only differences being in camera angles, character outfits and minor line changes. As such, the following recap is a near duplicate of the previous episode's recap, the only alteration being in the number of times the group's summer has looped so far:
It was a hot summer day and Kyon and his sister were planted in front of the couch watching a baseball game for no apparent reason. Before the phone even rang, Kyon had a feeling that Haruhi would be calling him, and soon enough she did. Without even waiting for him to speak, she tells Kyon that they and the rest of the brigade are meeting that day at the station. She immediately calls back reminding him to bring his bike, money and swimwear. Hadn't he already done this?
Kyon bikes over to the group's designated location to find that he is the last one to get there. As could be predicted by Haruhi's orders over the phone, she has scheduled them to go to the pool that day. However, given that only Koizumi and Kyon had bikes, the two of them were ordered to race each other to the pool: Kyon carrying Haruhi and Yuki; Koizumi carrying Mikuru.
Having reached the pool, Haruhi immediately dives in, completely ignorant to the "No Diving" sign. Kyon complains about how troublesome Haruhi can be, but Koizumi is grateful that she is taking so much joy out of such an ordinary activity. As the two relax in the shade, Kyon notices Yuki at the other side of the pool, seeming rather bored. It is then that Kyon feels that sense of deja vu once more. But as Haruhi introduces two girls to himself and Koizumi, Kyon simply brushes off the thought.
The group later meets at a local restaurant where Haruhi shows them a list of activities she would like to accomplish before the last two weeks of summer end. Koizumi takes a closer look at the list, as if suspicious of something, only to hand it back to Haruhi. As normal, Kyon pays for everyone's drinks and they leave the restaurant, all going their separate ways. Before he loses sight of her, however, Kyon calls out to Yuki for no reason he can think of. At a loss for words, he simply asks how she is doing, to which she replies that she is fine. Not knowing what else to do, Kyon heads home.
The next day, Kyon receives a call telling that the location of the nearest O-bon festival has been found-the first activity on Haruhi's list. Before going to the festival, Haruhi takes Yuki and Mikuru yukata shopping while Kyon and Koizumi wait inside the store. Upon exiting the changing rooms, the three women showed up with matching outfits as per Haruhi's decision. Kyon takes special notice of Mikuru and her outfit.
At the festival, Kyon notices the tower, stand and overall ambience of the festival. Although he hasn't been to one since he was much younger, it is as if he just attended an O-bon festival just the other day. While Haruhi drags Mikuru to the goldfish stand, Koizumi asks Kyon if he would like to follow them. He declines and asks Yuki if she wants something to eat. Looking even more bored Yuki walks up to a stand and purchases a mask. At the least Kyon felt like he should have bought it for her for some reason.
Wanting to finish something else on her summer to-do list, Haruhi takes the others to set off fireworks. Afterwards, she announces that tomorrow they will have a cicada-catching contest, with the winner being brigade leader for the day. All the while, Kyon has a strange feeling, that he cannot put his finger on exactly.
The next day, unsurprisingly, Haruhi ends up winning the competition. In the spirit of "catch-and-release," Haruhi decides to release all their captured cicadas. As she does this, however, Kyon is more reminded of Pandora releasing her madness onto the world than anything else.
The following day, the group took on a part-time job at a local supermarket attracting customers while in frog suits. After undergoing such a grueling task, Haruhi, who did not take part in that work, told them that one of the frog suits would be their pay, disappointingly enough.
That night, Kyon receives a call from Mikuru, who seems distressed about something. Koizumi ends up taking the phone next, telling Kyon where to meet them that night. Regardless of how late it was, Kyon takes his bike to meet with Mikuru and Koizumi as well as Yuki. There, a teary-eyed Mikuru tells Kyon that she can no longer time travel. To elaborate, Koizumi explains that they are stuck in the same timeframe, repeating the events happening between the morning of August 17th and midnight on the 31st. Mikuru attempts to further explain, having been the one to inform Koizumi in the first place, but with her strict confidentiality code, this does not help much.
Kyon asks if they may be stuck in one of Haruhi's spaces, to which Koizumi says that they most definitely are not. He further clarifies, saying that a slice of time has been cut out and is repeating itself, with everyone's memories being reset as well. Kyon then asks if this is related to Mikuru's work as a time traveler, to which Koizumi again tells him no. If anyone, Koizumi says that it is most likely Haruhi's work, unknowingly repeating the last two weeks, wanting the summer to last longer.
As bizarre of an explanation as it is, it definitely explains why Koizumi and Kyon have been experiencing deja vu lately. Kyon asks Koizumi if others could be experiencing this as well, but he replies saying that it is probably more likely for those closer to Haruhi. In particular, Koizumi suspects someone to remember every "reincarnation" from the start: the Integrated Data Sentient Entity-Yuki Nagato.
Talking it over with Yuki, the only person to have remembered every repeated incarnation, the others find that they have been repeating the same two weeks 15,527 times. Amazed, Kyon asks if she has been knowingly repeating the same actions for so long. Yuki corrects him, however, telling him that each incarnation had a slight difference, with some events not taking place at all in some incarnations. As Kyon heads back home, he cannot help but be amazed at Yuki, having been repeating the same days for so long. 15,527 multiplied by two weeks... 595 years! Whether Kyon likes it or not, things have finally become burdensome for him again.
The next day was stargazing at Yuki's apartment with help of Koizumi's old telescope. While there, Haruhi talks to Kyon about the possibility of aliens and UFOs unknown to humans simply because they were hiding under a planet's surface. As it got later, Haruhi and Mikuru slept on the rooftop while Kyon and Koizumi discussed what they should do. Completely at a loss for how to escape this timeframe, Koizumi suggests that Kyon hug Haruhi from behind and whisper something along the lines of "I love you" into her ear. At such a drastic measure, Kyon immediately declines. Koizumi replies, asking if he were to do it instead. As Kyon glares at him, Koizumi says that he was only joking. Besides being a bad actor, it would only unnecessarily confuse Haruhi. While Haruhi and Mikuru slept, Kyon and Koizumi continued to look out at the night sky, as if the answer was out there somewhere.
The following day was spent at the batting cages-yet another repeated event to live through. While there, Kyon asks Yuki why she did not tell anyone of the time loop when it first happened. Yuki merely says that it is her job to observe.
So the rest of the summer went, with the brigade going to no end to accomplish the next item on Haruhi's list. Finally, the day of the 30th came-the day Haruhi's list finally comes to a close. She asks the others if they wish to do anything else, but they remain quiet. Haruhi continues, saying that they did a lot in those two weeks, but Kyon knows better, thinking "You're not satisfied yet, are you?" As Haruhi grabs her bag and leaves, Kyon stands up and is about to follow her. If she isn't stopped now, then how many more times will they have to repeat the same two weeks? There it is again-Kyon's feeling of deja vu. But what exactly would he do to prevent everything from repeating once more?
August 31st: nothing left to do but homework. Feeling completely hopeless, however, Kyon decides to let the homework wait. Perhaps the "him" of the future will deal with it.