第 1837 集: Rantarou與好友們為夜間巡邏設定密碼，六年級生隨即抵達

1837

To stop the trespassers, Rantarou and the others decide on passwords and, two at a time, they go on a night patrol. Then, the 6th years arrive. Not knowing whether the 6th years are impostors or not, the Ha class check their identities using the passwords. (Source: Nintama Rantarou Wiki)