After spending their first year of high school in peace and quiet, Haruka and Makoto run into Nagisa, a new student who was a member at a swimming club with them when they were kids. That swimming club is being torn down, so the three of them sneak in to dig up a time capsule that they buried in the back, which is when they are reunited with Rin, the fourth member of their group who left to study abroad.

The Iwatobi Swim Club has a full roster now.As they begin to practice, they run into a little trouble.After a certain member claims that his swimsuit is to blame, the club makes a trip to buy new swimsuits.

As prefecturals draw near, Haruka and the other swim club members continue to improve. Meanwhile, Rin reveals his motivations for swimming. The swimmers must now show what they have accomplished at the tournament.

Prefecturals are over and the Iwatobi Swim Club members are pleased by the progress they have made. A local summer festival gives them an opportunity to relax. When Nagisa finds out that Rin is also at the festival, he orders Rei to follow Rin and make sure that Haruka and Rin do not meet.

After hearing about what happened in the past, Rei goes to Samezuka Academy to ask Rin what he wants. The night before Iwatobi and Samezuka leave for regionals, Rin calls Rei to explain how he feels about the relay. And then, Samezuka announces its lineup for the relay.

The crew ponders how to attract new members to the Swim Club. Haruka is called in by Amakata-sensei to discuss his intended career path, but as always, Haruka moves to the beat of his own drum. Meanwhile, Coach Sasabe brings an interesting opportunity to the boys…

The members of the Iwatobi Swim Club ponder over the cause of Nagisa’s odd behavior at the end of practice that day. Though they time their chance well to ask Nagisa what’s happened, Nagisa stubbornly refuses to explain why he’s upset...

While Haruka and the boys redouble their training in the wake of prefecturals, Makoto notices Gou looking troubled and asks her what’s wrong. She tells him that Coach Sasabe has been so busy with his Swim Club lately, he hasn’t been by to approve their new training regimen. Makoto offers to go see him for her, but what he finds at the Swim Club is...

As the tournament continues, Sousuke finally tells Rin about how he’s passed their years of separation. Rin is concerned at Sousuke’s nonchalant attitude toward certain things and tries to speak his mind. Meanwhile, the Iwatobi Swim Club looks toward the relay final.

Upon Rin’s invitation, Haruka finds himself venturing to “a certain country.” Knowing that Haruka has hit a wall worrying about his future, Rin opens up and speaks to him about his own thoughts and feelings. Afterward, Rin quietly asks Haruka what he will do about his own future...