Big Hero 6: Do you remember?

This is going to be a quick random idea or a full-blown story. Years after the fall of Callaghan, his rise is something of legends as he returns to teaching with the help of Hiro and his fellow students who all know what happened was terrible, but caused by something just as much so to him. Everyone is reaching near their final years at SFIT and Hiro is beginning to worry he may be running out of time, but there is another who fears just as heavily but lacks the ability to admit what she feels.