琴跳入海中救溺水的怜，却意外回想起小时候对海的可怕映象，顿时全身僵硬无法动弹，所幸遥听到了琴呼唤怜的声音及时醒来，与渚一起救下了琴和怜。在另一座无人岛上，四人迫于暴风雨不得不呆在废弃的休息室里，一夜难眠，在渚的提议下，怜无奈吐露了小时候难忘的糗事，遥与大家分享了自己的恋爱史，渚表演了企鹅特技，最后，琴说出了小时候与遥一同经历的关于海的可怕经历。

为准备地区大赛，岩鸢游泳部请来吾朗当教练，晚上大家聚在一起吃火锅时，江找出了曾经游泳俱乐部的相册和大家分享，凛的影子充斥在岩鸢游泳部，怜愈发不明白这四人到底发生了什么，遥告诉他凛曾和他们是同学后来又转入了同一所俱乐部，在凛的坚持下四人游完了最后一次接力赛，之后凛便去了澳大利亚，某次凛回国探亲时碰到了遥，两人相约游泳，可遥的胜利却深深的伤害了凛。得知一切的怜，怀着自己的心思找到了凛……

一段回忆之后，期待已久的县大赛到来了。由于凛被禁止参加接力赛，导致凛在比赛中的严重发挥失常，赛后甚至说错了放弃游泳的话。遥们赶到后听到了只言片语，同样让遥灰心。但怜的话，又让遥找到了拯救凛的方法，那就是……

真琴一如既往的来接遥上学，随后真琴与遥和在车站等待自己的渚和龙崎汇合来到了凛的学校鲛柄。再鲛柄部长的热情下真琴四人和鲛柄游泳部的成员展开了练习赛。社团招新会上为了能吸引新生入社真琴四人像新生展示了自己的肌肉却依旧没有人来报名。在社区的游泳比赛上，凛与遥再次展开了属于两人的较量，而最终获胜的会是谁呢？

县大会召开在即，各学校都开始制定严密的训练计划。小江决定为游泳部的各位量身制定肌肉训练计划，结果检查便当发现大家都没把锻炼肌肉当回事。另一方面，凛带领新入部员去选购泳衣，事后与宗介两人闲聊，回想起了小时候的事。在小时候凛与宗介许下约定，要为宗介做一件事。可是这约定直到凛出国前也没有实现。如今，宗介似乎想用掉这个约定……

第一天的比赛结束，各校都在总结检讨之前的比赛。宗介的状态一直很奇怪，凛看在眼里却没有询问。为了第二天的接力，凛决定将之前负责仰泳的鱼住换成了百太郎。小爱目睹后辈超越自己，心有不甘。第二天的接力比赛开始了，鲛柄和岩鸢的接力对决令人激动不已。真琴打头，可是在起步的时候慢了半拍；之后其他队员奋力追赶，还是以微小的差距屈居第二。而在比赛过程中，宗介却没有100%投入，甚至有一瞬间失速。宗介有着心事却不跟凛透露，他究竟出了什么状况？

岩鸢游泳部打进全国大赛，大家的努力得到了全校师生的肯定和期许，遥对此却不以为然。宗介因伤要离开鲛柄游泳部了，凛十分伤感。一天的训练结束后，遥留下独自练习。怜很担心遥的状态，他不愿看到遥放弃自己游泳的信念。宗介为了凛专门找到遥，他希望遥能勇敢地迈开步伐，正视自己的心意……

初中一年级的夏天，在大赛混合泳接力上没能得出结果的遥决定以接力赛队员的身份进行集训。那天晚上，醒来的遥向游泳池走去，看见了郁弥一个人仰望星空。

Haru, Makoto, and Asahi visit Shimogami University in hopes of talking to Ikuya, but even after looking all over campus, they can't find him. Hiyori, however, notices them and makes it his mission to keep them from seeing Ikuya.

Hiyori still remembers the first time he saw Ikuya smile. Both boys grew stronger through rigorous training while they studied abroad in America... but seeing Haruka threw Ikuya off his stride. Now Hiyori wishes Ikuya would just forget about Haruka for good.

After the breakup of his middle school swim team, Ikuya decided to get stronger on his own and not rely on anyone. But Haruka, breaking out of his freestyle comfort zone to swim in the individual medley, tells Ikuya that he's not alone.

Makoto has been unable to get in touch with Haruka following the friendly race at his training camp, making him worry that Haruka is dwelling on what happened. Then Nao approaches Makoto to tell him about a rumor he heard.

Nagisa, Rei, and the rest of the Iwatobi Swim Club have come to cheer on their former teammates at the All-Japan Invitational. Makoto tells them the story of how ever since Haruka swam for the first time, he'd been swimming only freestyle.