Uchuu he Ikou/Uchuu Kaijuu wo Yattsukero!!

Senbei invites Midori on a trip to space. Arale and Gatchan tag along unexpectedly. Everyone is enjoying the trip until Senbei urgently needs to use the bathroom and they have to make a stop on a planet. There, they are attacked by a monster monkey who wants to eat Midori.