Kohaku has located the treasure left behind by Byakuya and the others, but it's encased in concrete. Senku has to devise a plan to quietly get at the contents inside, so as to not alert the guards.
It came from the transparent, ice-like room.
.جاء من تلك الغرفة الشفافة الشبيهة بالجليد
Aus einem durchsichtigen,
eisartigen Raum.
De la pièce
couverte de glace transparente.
Proviene... dalla quella stanza 
che sembra fatta di ghiaccio trasparente!
Veio de uma sala transparente, que nem gelo.
Это из прозрачной, словно лёд, комнаты!