Hypnotized? I don't know, Rhoda is probably filled with years of seething, repressed resentment at being treated as nothing more than a jiggly stage prop in your cheesy magic act and has been quietly waiting for just this opportunity.
"Don't concern yourself Rhoda, you were under that madman's control. You couldn't help yourslf."
"Oh, well officer, Blackstone wasn't that ba...oh, you mean the evil scientist. Yes. Couldn't stop myself. I was totally helpless. Damn him. Can I go?"