[Shin Henshin]

Man, Argo's whole concept and plan would have made Ghost as a series so much more interesting if it wasn't regulated to just a film plot. I liked Ghost overall, it just wasn't very strong. If they integrated Argo into the series as the real looming villain behind Adel, I think it could have changed things for the better.

Takeru's main adversary would have been the original choice to inherit the power of Kamen Rider Ghost, driven mad by the prospect of death and the transition to the form of a ghost being a step towards immortality. Why let your life burn bright when you can throw it away and live for eternity? Add the fact that Takeru's body being the perfect vessel for the ultimate eyecon and a bit of coaxing from Argo and you could have had a finale arc where Takeru had to choose between letting Argo fulfill his ambitions and convert everyone to ghosts so he and his loved ones could live forever or sacrifice his chance to return to life so everyone else could live.

Plus you could have kept Adel's whole plot in-tact and had a three-way confrontation: Takeru wanting to unite the human and ganma worlds, Adel wanting to conquer the human world and rule everything and Argo wanting to basically kill the inhabitants of both worlds to grant them eternal ghost life.