Fate/Kaleid Liner Prisma Illya 2wei! Herz!

Illya's fun summer break comes to a sudden end. The aftermath of their battle against the Heroic Spirit of the 8th Class Card disappeared overnight from Mt. Enzou.

One of Ainswoth's dolls, Beatrice, attacks Illya and the mysterious girl, Tanaka. Both are driven into a corner by her overwhelming strength. Just as they run out of options, someone calls Beatrice back, freeing them from their peril.

Led by Gil, Illya and Tanaka successfully infiltrate the Ainsworth mansion. Their goal is the room where Miyu's held captive, but standing in their way is Beatrice and Angelica.

Thanks to sniping from Kuro, Illya's group managed to slip away from Beatrice and retreat from the Ainsworth mansion for the time being. Then they try to regroup at the school building Bazett and Kuro and have been using as their base.

Bazett's barrier was supposed to prevent surprise attacks from the dolls, however Illya finds a little girl, Erica, sneaking into their school. For some reason Erica calls Illya "Onee-chan", and the two of them quickly hit it off.

The man who came to pick up Erica proclaims himself as Darius, head of the Ainsworths and Miyu's kidnapper. Using his great power, Darius activates an ice-barrier Noble Phantasm.