地球署に赴任したバンは、ホージーたちが取り調べをしていた暗殺者ドロイドを破壊してしまう。4人のメンバーはバンの無鉄砲なやり方・態度に反発しつつ、地球に落下した巨大物体の調査にあたる。その頃、アリエナイザーの死体が警視庁からデカベースに運ばれてきた。そして異変が起ころうとしている!
Three unidentified objects have landed in Japan. Upon investigation, they escape. An object is found near the crime scene, which had an audio recording on it, with a plan to take over Earth. Luckily, the Dekarangers are on the case, fighting their first Alienizer, Moyeda. But, Ban isn't accepted by the others are a leader nor member. Will they ever? Also, what's Ban's will to fight? Does he have any?
