Ep. 4: The Brigade experiences another identical loop with minor changes and new outfits.
Aired on July 3, 2009

The SSS members, excluding Haruhi, realize they are stuck in a time loop again. This marks the 15,499th repetition of the same events, where the group fails to find a way out of the endless summer. During a restaurant scene, Kyon cannot prevent Haruhi from leaving, which causes the world to reset into another summer cycle. Consequently, Kyon falls asleep without completing his homework on the final day of the season. The narrative repeats the previous episode's occurrences with slight variations in clothing and minor details, emphasizing the futility of their current situation as they remain trapped in this infinite temporal cycle without resolution.
Episodes
- Ep. 1 · Kyon and Mikuru travel back to Tanabata three years prior to assist Haruhi
- Ep. 2 · Haruhi forces the SOS Brigade through an exhaustive list of summer activities over two weeks.
- Ep. 3 · Haruhi traps the group in an infinite loop of the final two weeks of August.
- Ep. 4 · The Brigade experiences another identical loop with minor changes and new outfits.
- Ep. 5 · The time loop repeats for the 15,513rd time as Kyon senses deeper familiarity with the recurring events.
- Ep. 6 · The time loop repeats for the 15,521st time as Haruhi dismisses group activities
- Ep. 7 · The time loop repeats for the 15,524th time as Kyon observes Yuki
- Ep. 8 · The loop repeats for the 15,527th time with recurring scenes involving Kyon, Haruhi, and Yuki.