Fourth "interrogates" Amano by playing Russian roulette. Gasai steals an officer's gun and breaks him out. They go on the lam.
While hiding, they meet up with Ninth, who explains: Fourth's son is dying and now he wants to win.
They all have Dead Ends in their diaries now.
Fourth comes for them, but Ninth arranges things so the other cops see what he's up to and arrest him. His diary shows what happens on his cases, so it's useless now.
He asks Ninth for one final favor, and pays with his life, destroying his own diary.