Supana returns to his master Kyoka Edami to have her repair his Valvarusher, which was heavily damaged during his battles with the Three Dark Sisters. As he arrives in her laboratory, he becomes intrigued by the blueprints of a new weapon she is developing.
A giant snake suddenly appears from the sky and attacks people with its petrification rays. Houtaro transforms into Gotchard and confronts the snake, who speaks in an eerie voice.
"Are you Kamen Rider...?"
What is the true identity of the giant snake?
