After botching another match, bowling club captain Mai struggles to keep the club fun for all of its members.

The girls find themselves in the past facing immediate danger when a handsome young 'B' comes to their rescue.

The girls deal with Suguri's eccentric sisters while brainstorming ways to get home without affecting history.

Mai forgets her promise and asks Sumomo to build a bowling lane while Rina wrestles with her inner struggles.