Mix: Meisei Story 2nd Season - Nidome no Natsu, Sora no Mukou e

Following the achievement in the year's summer tournament, many students apply to join the Meisei High School baseball team.

Nishiki Kenji, who had quit the team in a dispute with its manager while in the middle grade years, returns to the team as well, and the team carries on with newly joined members.

The following spring, Tachibana Otomi, Natsuno Ichiban, Mita Arisa, and Akai Ryou enter the high school.

Ichiban aspires to be a pitcher.

Arisa is the younger sister of Mita Hiroki, and Ryou is the younger brother of Akai Tomohito.

Tomohito reveals to Touma how he and Ryou are brothers by remarriage just like Touma and Souichirou are, that their relationship is discordant due to troubles in the past, and that Ryou, who had quit baseball feeling inferior to Tomohito, still loves the sport and has a talent for it.

Tomohito asks Touma to persuade Ryou to join the team by using him as the "bad guy", and Touma obliges.

The baseball team begins its new season with new members including Ichiban and Ryou.

The Eastern Tokyo block preliminaries begin for the summer national tournament, and the Meisei High School team advances steadily.

Memories of past summers are recalled as the team confronts formidable opponents Kenjo, Seinan, and Eishin, striving to finally win the coveted slot in the national tournament.