S1E10 Irritated Heart Rate!/Plot

The episode started with Rin's introduction as the new transfer student of Iwatobi Middle School. Rin tells the class that even though he has a girly name, he is in fact a boy. Makoto remembers that Rin had been in some tournament with them. Rin joins their school's swim club as well. Rin asks Haruka to join him in a relay, but he refuses, stating that he only 'swim free'.

Makoto and Nagisa sees Rin swims and praise him. Only Haruka remain silent. Afterwards, Haruka opt to run home, following Rin's habit and forgoing his bicycle. Nagisa tags along as well. In the locker room, Nagisa approaches Rin and asks if he is forming a relay team, wanting to join. Rin replies that he can join if he place first in the next breaststroke time trial. Excited, Nagisa tells Haruka that he is going to work hard, but Haruka remains indifferent.

Rin asks Makoto why Haruka is 'so obsessed with free'. Makoto replies that he didn't think Haruka likes swimming free, but he never asked either. Rin wonders is there is any way to get Haruka to participate and Makoto questions Rin as to why is he so obsessed with swimming in a relay. However, Rin just says that he has his reason, and left it at that.

Standing in front of a sakura tree, Rin tells Haruka and Makoto that he is leaving for Australia the day after the tournament as he is going to a swimming school there. He says that this is their last chance to swim together, and tell Haruka that if he joins the relay, he will 'show you a sight you've never seen before.'

At the pool, Goro decided to continue coaching the team for their relay competition. He continuously urges them to practice more and take note of their faults like swimming form, kicks and time. He gets exasperated soon and tells them that they 'don't know what you're doing.' Goro sets up recording equipment at the pool, letting the swimmers check out their form from multiple angles. It proves effective but Rei comments that the way Haruka swim was more beautiful before.

On the way home, Nagisa asks Rei what is wrong and Rei replies that he does not understand why Rin suddenly decide to take part in the relay. He complains that their goal is to make it to the national as a team but everyone is talking about Rin instead.

The team, along with Gou and Miho are over at Goro's house, eating hot pot even though it is in the middle of summer. When Nagisa accidentally upsets a stack of old magazines, Goro realises that the reason he found Miho familar was because he saw Miho being a model for swimsuits in his magazines.

Gou discovers a photo album of the swimming club. They start looking over the pictures and Rin is in several of them.

On the way home, Rei asks the other three what happened to their relationship with Rin, as the old photos showed how close they were before. Haruka says that he will tell Rei if he is interested, and Rei replies that he is, saying that he is tired of 'being the only one on the outside.' Haruka tells Rei about Rin's obsession with swimming relay, and says that Rin only told them the reason right before the final. Rin tells them that it is because his father was one of the first members of the club, and he was always part of a winning relay when he was in sixth grade. Rin wanted to follow in his father's footstep so that he might be able to share his father's dream of becoming an Olympic swimmer. Haruka talks about the sight that Rin promised to show, and says that he felt like he really did see it. Nagisa and Makoto both agree.

One day, Haruka ran into Rin and Rin wants them to swim together again. However, the objective this time is 'to see who's faster'. Rin lost the race. He tells Haruka that he is quitting swimming, and runs off. Now, Nagisa finally knows the reason that Haruka quit the swim club in middle school. Makoto comments that Haruka stopped because he felt guilty. Rei is still confused about why Haruka is upset about losing, and why Rin is also entering the relay. Haruka has no answer but he states that he is looking forward to racing Rin again.

Nagisa tells Rei not to brood on it any more as it is all in the past, and they do not plan on getting Rei involve. However, this angers Rei instead as he shouts that he is already involved.

The next day, Rei is not at the pool practising and Nagisa hurriedly say that he might have given Rei some spoilt ice cream. However, Nagisa seems to have an idea of where Rei is. Rei is at Samezuka Academy and meets with Rin, telling him that they need to talk.