"Fire Company M is a special squad of the Tokyo Fire Department. The “fated three,” Toake Daigo, Onoda Shun, and Nakamura Yuki, have been gathered to prepare for an unprecedented calamity that may hit Tokyo one day. Let’s review their bond once more."
meaning a total of three 
will enter the scene.
.أي أنّ ثلاثة سيدخلون المكان
Es decir, solo van a entrar tres.
Eso significa que solo tres entraréis.
No total, três vão entrar no local!
то есть в здание заходят трое.