Professor Robert Callaghan, or also better known by his supervillain name Yokai, is the main antagonist of Disney's 54th full-length animated feature film Big Hero 6 and a minor character in Big Hero 6: The Series. He is also the former archenemy of Hiro Hamada and Baymax.
He is a former university teacher presumed dead in a fire; until he later re-emerged using a vast army of microbots in his plan to take revenge on Alistair Krei, whom he blames for the supposed death of his daughter Abigail Callaghan.
What nakes him sympathetic?[]
- He was a true friend to Professor Granville.
- He lost his daughter when an experiment goes horribly wrong and she was trapped in another dimension.
- He blames Alistair Krei for the death of his daughter and all of his actions are caused by his desire to avenge her.
- When Big Hero 6 rescue his daughter, he is rejoiced to see her again and feels remorse for his actions as he is driven away by a police car.
- He apologises to hiro for causing the death of his brother and hopes that some day he would forgive him.
- He realises that Big Hero 6 are good and even defends them in front of Chief Cruz when they are declared fugitives.