ジオウとして戦いつづける道を選んだソウゴだったが、
この決断がターニングポイントとなり、時の流れは未知の局面へ。
ソウゴたちのまえには、歴史に存在しないはずの“仮面ライダーシノビ”から生み出された“アナザーシノビ”が現れる。
さらに、ウォズとうり２つの謎の“ウォズ”も現われて……。
It was Sougo himself who ultimately made the decision to continue fighting as Kamen Rider Zi-O! However, his choice came at a cost, as the flow of time has suddenly been changed! Suddenly appearing before Sougo and the others appears Another Shinobi, who was created from the abilities of Kamen Rider Shinobi, who shouldn't even exist in this timeline's history! Also, another mysterious Woz appears before Sougo and the others and stands before the present Woz...!
