High☆Speed! Movie: Free! Starting Days

Haruka Nanase and Makoto Tachibana enter middle school after years of swimming together, only to discover that growing older has made the sport more complicated. Makoto adapts quickly to new classmates, while Haruka withdraws from the swim club and struggles with feelings left over from his past.

An argument eventually draws Haruka and Makoto into a relay team with Asahi Shiina and Ikuya Kirishima. The four boys have talent but very different attitudes toward swimming, and success depends on learning to match more than their strokes. Training together forces Haruka to reconnect with others and shows each boy what kind of swimmer, teammate, and friend he wants to become.