Basically Mister Freeze finds himself dying from his condition and determined to ensure he and Nora must survive manages to learn Batman's identity and swaps bodies with him (without the knowledge of the rest of the Bat Family). After Bruce seemingly dies inside Victor's old body Victor finds himself convinced enough to carry on Bruce's work as the 'Superior Batman', using Wayne tech to secretly fund Nora's treatment and put his hated rivals Gothcorp out of business whilst working at Batman in his own scientific if more amoral way.
How might Victor do as Batman, how would he adapt the concept, how quickly would he ostracize the rest of his team and Alfred, or do you think he might actually do a decent job?