This is one of the best Mabels I've ever seen. It doesn't hurt that her voice is so pleasing (which is not easy with Mabel), but what I'm really impressed with is a) her stepping out of the chorus for her first solo line, and b) she seems utterly sincere in wanting to do what Frederick is actually asking for -- help in guiding him to a virtuous future. It also helps that Frederick seems delighted by her. A lot of the Fredericks seem a bit taken aback by Mabel singing those long coloratura riffs. I also really like the choice of having the daughters dressed for hiking. That's a nice modernization. I wish I could have seen everything they were doing behind Frederick's song, because it looked really fun.
