Yup I played it years ago when it came out. My copy is somewhere among my old games. I remember it being left kind of hanging at the end. They had planned on making more as you said, because it was based on a french comic of the same name, and they either couldn’t finish the story arc in one game, or they were looking to make more money by spreading it across many games. Either way the cell shading, while it was different, and I enjoyed it, was not well received by the majority of most games.